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                                                                   EXHIBIT 4.15

                                NTL INCORPORATED

                       PARTICIPATING PURCHASER AGREEMENT

                                                             September 26, 2003

W.R. Huff Asset Management Co., L.L.C.
1776 On the Green
67 Park Place
Morristown, New Jersey  07960
Attn:  Joseph Thornton

Ladies and Gentlemen:

                  NTL Incorporated, a Delaware corporation (the "Company"),
proposes to distribute rights ("Rights") to holders of its Common Stock of
record as of the close of business on the Record Date to subscribe, in the
aggregate, for that number of shares of Common Stock ("Subscription Shares")
determined by dividing the aggregate dollar amount of the offering by the
Subscription Price as set forth in the Prospectus (such offering, the "Rights
Offering"). Capitalized terms are defined in Section 1 below.

                  In the Rights Offering each holder of Common Stock on the
Record Date (other than certain overseas holders) will receive certificates
("Subscription Certificates") evidencing that number of Rights set forth in the
Prospectus for each share of Common Stock held by such holder as of the Record
Date. The Rights will expire at the time and on the date set forth in the
Prospectus (as may be extended by the Company, the "Expiration Date"). Such
holders will have the right to exercise the Basic Subscription Privileges and
exercise the Rights to acquire shares of Common Stock, and to exercise the
Over-subscription Privileges to acquire additional shares of Common Stock in
the event that all Rights are not exercised prior to the close of business on
the Expiration Date (the "Expiration Time"). The terms of the Rights Offering
provide that under no circumstances may any stockholder acquire shares of
Common Stock in the Rights Offering such that, after giving effect to such
acquisition, it beneficially owns in a percentage of the Company's outstanding
shares of Common Stock in excess of the Subscription Limit.

                  On the date hereof, the Company will file with the Securities
and Exchange Commission ("Commission") a registration statement on Form S-1 and
a related preliminary prospectus for the registration of the Rights Offering
and the shares of Common Stock to be issued in connection therewith to the
public and the Underwriters under the Securities Act. Such registration
statement (as amended, if applicable, in accordance with Section 4(b)) and the
final prospectus relating to the offering constituting a part of the
registration statement, as from time to time amended or supplemented pursuant
to the Securities Act in accordance with Section 4(b), are referred to in this
Agreement as the "Registration Statement" and the "Prospectus," respectively.

                  Concurrently herewith the Company is entering into an
Underwriting Agreement in the form set forth on Schedule A dated as of the date
hereof by and among the Company and the Underwriters (as may be amended from
time to time in accordance with Section 4(b), the "Underwriting Agreement"),
pursuant to which the Underwriters will agree to purchase shares of

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Common Stock in the amounts set forth therein in the event that all Rights are
not exercised prior to the Expiration Time.

                  The Underwriters' commitment under the Underwriting Agreement
is conditioned upon the exercise by certain significant stockholders of the
Company, including the undersigned, W.R. Huff Asset Management Co., L.L.C., a
Delaware limited liability company ("Huff" or the "Participating Purchaser"),
on behalf of certain of its affiliates and managed accounts for which it acts
as investment adviser (the "Accounts"), of Rights distributed to them in the
Rights Offering.

                  Concurrently herewith, the parties are entering into a
Registration Rights Agreement, providing for certain registration rights
covering the resale of the shares of Common Stock acquired pursuant to the
Rights to be exercised in connection with this Agreement.

                  In connection with the transactions contemplated by this
Agreement and pursuant to Section 5.06(b)(ii)(B) of the Indenture governing the
19% Senior Secured Notes due 2010 issued by the Company (the "Indenture"), the
Company has obtained a letter from Lehman Brothers, dated September 26, 2003
(the "Fairness Opinion") as to the fairness from a financial point of view to
the Company of the transactions between the Company and each of the Committed
Stockholders entered into pursuant to this Agreement, subject to appropriate
assumptions and limitations with respect thereto.

                  For good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Participating Purchaser (on
behalf of certain of its affiliates and managed accounts for which it acts as
investment adviser) and the Company agree as follows:

         Section 1.  Certain Defined Terms.

                  The following terms have the following meanings:

                  "Accounts" has the meaning provided in the preamble.

                  "Basic Subscription Privilege" means the basic subscription
privilege with respect to the Rights, as described in the Prospectus and set
forth in the Subscription Certificates.

                  "Closing Date" has the meaning provided in the Underwriting
Agreement.

                  "Commission" is defined in the preamble.

                  "Committed Aggregate Exercise Price" is defined on Schedule F.

                  "Committed Stockholder" means each stockholder of the Company
who as of the date hereof has entered into a participating purchaser agreement
with the Company on terms substantially the same as the terms of this Agreement
and shall also include the Participating Purchaser.

                  "Committed Stockholder Agreement" is defined in Section 4(d).

                  "Commitment Fee" is defined in Section 2(c).

                  "Commitment Securities" is defined in Section 2(a).

                  "Common Stock" means the common stock, $.01 par value per
share, of the Company.

                  "Company" is defined in the preamble.


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                  "Effective Date" means the effective date of the Registration
Statement.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

                  "Exercise Date" is defined in Section 2(a).

                  "Existing Registration Rights Agreement" means the Equity
Registration Rights Agreement by and among the Company and the Stockholders
listed therein dated as of January 10, 2003.

                  "Expiration Date" is defined in the preamble.

                  "Extension Fee" is defined in Schedule F.

                  "Fairness Opinion" is defined in the preamble.

                  "HSR Act" means the Hart-Scott-Rodino Antitrust Improvements
Act of 1976, as amended and the rules and regulations thereunder.

                  "Huff"  is defined in the recitals.

                  "Indenture" is defined in the preamble.

                  "Lead Underwriters" has the meaning provided in the
Underwriting Agreement.

                  "Material Adverse Effect" means a material adverse effect on
the condition, financial or otherwise, business, general affairs, management,
financial position, shareholders' equity or results of operations of the
Company and its Significant Subsidiaries (as defined in the Underwriting
Agreement) taken as a whole.

                  "Over-subscription Privilege" means the oversubscription
privilege with respect to the Rights, as described in the Prospectus and set
forth in the certificate evidencing the Rights.

                  "Participating Purchaser" is defined in the preamble. The
Company understands that the Participating Purchaser is entering into this
Agreement on behalf of the Accounts.

                  "Participating Purchaser Information" is defined in Section
6(a).

                  "person" means any person, corporation, limited liability
company, partnership, trust or other entity.

                  "Preliminary Prospectus" has the meaning provided in the
Underwriting Agreement.

                  "Prospectus" is defined in the preamble.

                  "Record Date" means the record date established by the
Company for the Rights Offering.

                  "Registration Statement" is defined in the preamble.

                  "Revised Allocation Amount" is defined in Section 2(a).

                  "Rights" is defined in the recitals.

                  "Rights Offering" is defined in the preamble.

                  "Rights Plan Amendment" means the Amendment to Rights
Agreement dated as of the date hereof between the Company and Continental Stock
Transfer & Trust Company.

                  "Securities Act" means the Securities Act of 1933, as
amended.

                  "Specified Conditions" means the conditions precedent set
forth on Schedule C.


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                  "Specified Covenants" means the covenants of the Company in
favor of the Underwriters provided in the Underwriting Agreement as listed on
Schedule D and as modified thereon.

                  "Specified Representations and Warranties" means the
representations and warranties of the Company in favor of the Underwriters in
the Underwriting Agreement, as listed on Schedule E and as modified thereon.

                  "Subscription Agent" means the subscription agent for the
Rights Offering as set forth in the Prospectus.

                  "Subscription Certificate" is defined in the preamble.

                  "Subscription Limit" means with respect to (A) a person who
beneficially owns less than 7.5% of the Common Stock outstanding as of the date
hereof, 14.9% of the shares of Common Stock outstanding on the Exercise Date
(taking into account any shares to be issued to the Underwriters) and (B) a
person who beneficially owns 7.5% or more of the Common Stock outstanding as of
the date hereof, a percentage which is equal to the lesser of (a) the
percentage of the shares of Common Stock outstanding as of the Exercise Date
(taking into account any shares to be issued to the Underwriters) that is 7.5%
more than the percentage of that person's beneficial ownership of the shares of
Common Stock outstanding as of the date hereof or (b) 19.9% of the shares of
Common Stock outstanding as of the Exercise Date (taking into account any
shares to be issued to the Underwriters). The term "beneficial ownership" is
used as defined in Section 13 of the Exchange Act and the regulations
promulgated thereunder.

                  "Subscription Price" means the Purchase Price per share as
defined in the Underwriting Agreement (as in effect on the date hereof) and as
calculated in accordance with the terms thereof (as in effect on the date
hereof).

                  "Subscription Shares" is defined in the preamble.

                  "Success Fee" is defined in Section 2(c).

                  "Third Party Claim" means a claim, cause of action or other
proceeding before a court or other governmental authority, whether threatened
or pending, brought or raised by any party (other than the Participating
Purchaser or its affiliates, the Company (other than through a stockholder
derivative action) or any of the Company's subsidiaries) in connection with the
Rights Offering or any transaction contemplated thereby.

                  "Total Cap Amount" is defined in Section 2(a).

                  "Total Rights Offering Size" is defined on Schedule F.

                  "Underwriters" has the meaning provided in the Underwriting
Agreement.

                  "Underwriting Agreement" is defined in the preamble.

         Section 2.  Purchase, Sale and Delivery of Commitment Securities.

         (a)      (i) Subject to the terms and conditions of this Agreement,
the Participating Purchaser agrees to take all action as may be required to
duly and effectively exercise the Basic Subscription Privilege with respect to
all of the Rights issued to the Accounts; such exercise to be effected in
accordance with the procedures set forth in the Prospectus (subject to Section
2(b) below) as of 4:30 p.m. on the Expiration Date or any other time before the
Expiration Time as may be agreed between the Company and the Participating
Purchaser (the "Exercise Date"). The Subscription Shares issued to the
Participating Purchaser as a result of its exercise of the Basic Subscription
Privilege with


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respect to its Rights in accordance with this Section 2 are referred to as the
"Commitment Securities."

                  (ii)     Notwithstanding anything to the contrary herein, the
Company will not effect the Rights Offering if it has a Total Rights Offering
Size such that (without giving effect to Section (2)(c)(iii)) the number of
shares of Common Stock issued or issuable upon exercise of the Basic
Subscription Privilege with respect to all Rights issued to the Participating
Purchaser and the other Committed Stockholders would together equal or exceed
the 20% limitation set forth in Rule 4350(i)(D) of the NASDAQ Stock Market
Rules (the "Total Cap Amount").

                  (iii)    Notwithstanding anything to the contrary in this
Agreement or in the Basic Subscription Privilege or the Over-subscription
Privilege, but without limiting Section 2(a)(ii), the Participating Purchaser,
together with the other Committed Stockholders, may not (and shall not be
deemed to be required to) acquire Commitment Securities upon exercise of the
Rights in an amount equal to or greater than the Total Cap Amount. Accordingly,
(A) the allocation of shares of Common Stock upon exercise of the
Over-subscription Privileges by the Participating Purchaser and the other
Committed Stockholders shall be adjusted by the Company downward (to zero, if
necessary) to a number so that the Total Cap Amount is not met or exceeded
(such aggregate number, the "Revised Allocation Amount") and (B) to the extent
that such allocations must be reduced, they shall be reduced pro rata among the
Participating Purchaser and all other Committed Stockholders who have exercised
the Over-Subscription Privilege, based upon the relative allocation amounts
requested by each such person against the Revised Allocation Amount.

         (b)      The purchase price for each share of Common Stock purchased
by the Participating Purchaser pursuant to the Basic Subscription Privilege
shall be equal to the Subscription Price and shall be paid by wire transfer of
same day funds to the Company on the Exercise Date.

         (c)      In consideration for the Participating Purchaser's commitment
to purchase the Commitment Securities and provided that the Participating
Purchaser acquires the Commitment Securities in accordance with the terms
hereof, within five business days after the Exercise Date, the Company will pay
to the Participating Purchaser a commitment fee as determined in accordance
with Schedule F (the "Commitment Fee"). In the event that the Company pays the
Underwriters a discretionary additional fee as described under the caption
"Additional Fees" on Schedule II to the Underwriting Agreement, then the
Company shall, subject to the prior approval of a majority of the disinterested
directors on the board of directors of the Company, pay an additional fee to
the Participating Purchasers equal to 0.25% of the Committed Aggregate Exercise
Price (such additional fee, the "Success Fee"); such Success Fee to be paid
within five business days after approval by such disinterested directors. The
Company shall submit payment of the Success Fee to the board of directors
promptly upon payment of the additional fees to the Underwriters described
herein. The Participating Purchaser shall provide the Company with notice of
the Accounts to which the Commitment Fee and Success Fee, if any, should be
credited no later than two business days before the Exercise Date.

         (d)      Delivery of the Commitment Securities to the Participating
Purchaser will be made by the Subscription Agent for the Rights Offering in
accordance with the terms of the Rights Offering set forth in the Prospectus.

         (e)      Notwithstanding anything herein, under no circumstances will
any Accounts (together with the Participating Purchaser, all other Accounts and
the affiliates of the Participating


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Purchaser) acquire (or be deemed to be required to acquire) shares of Common
Stock in the Rights Offering in excess of the Subscription Limit and the
Participating Purchaser's exercise of subscription privileges shall be adjusted
as necessary to provide that the Subscription Limit is not exceeded.

         Section 3.  Representations and Warranties.

         (a)      The Company hereby represents and warrants to the
Participating Purchaser that each of the Specified Representations and
Warranties is true and correct as of the date hereof.

         (b)      The Company hereby represents and warrants to the
Participating Purchaser as follows as of the date hereof:

                  (i)      the Company has been duly incorporated and is
validly existing as a corporation in good standing under the laws of the State
of Delaware and the Company has all requisite corporate power and authority to
enter into this Agreement and to consummate the transactions set forth in this
Agreement;

                  (ii)     the execution and delivery by the Company of this
Agreement, and the consummation by the Company of the transactions set forth in
this Agreement, have been duly authorized by all necessary corporate action on
the part of the Company;

                  (iii)    this Agreement has been duly executed and delivered
by the Company and constitutes a valid and binding obligation of the Company
enforceable against the Company in accordance with its terms;

                  (iv)     no authorization, approval or consent of any
governmental authority or agency is necessary to be obtained or made by the
Company in connection with the issuance of the Rights by the Company to the
Participating Purchaser or the issuance of the Commitment Securities by the
Company upon exercise of such Rights, other than as may be required under
federal or state securities laws and except for filings, if any, as required
under the HSR Act;

                  (v)      the execution and delivery of this Agreement by the
Company and the consummation of the transactions set forth in this Agreement by
the Company does not conflict with, or result in a breach of, (A) any law or
regulation of any governmental authority applicable to the Company, which
conflict or breach would have a Material Adverse Effect, or (B) any agreement
to which the Company is a party, which conflict or breach would have a Material
Adverse Effect;

                  (vi)     the Company has delivered the Fairness Opinion and
officers certificates to the indenture trustee in accordance with terms of the
Indenture, and accordingly, no default exists with respect to Section
5.06(b)(ii) thereof;

                  (vii)    when issued and paid for in accordance with the
provisions of Section 2, the Commitment Securities issued to the Accounts upon
the exercise of Rights as contemplated by Section 2 shall be duly authorized,
validly issued, fully paid, nonassessable, and free of any claims or
encumbrances, other than any claims or encumbrances resulting from actions


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taken by the Participating Purchaser or the Accounts with respect to the shares
to be received by it hereunder;

                  (viii)   the Rights Plan Amendment is in full force and
effect and has not been modified or amended in any material respect; and

                  (ix)     the Company has delivered to Participating Purchaser
true and correct copies of the Underwriting Agreement, the other Committed
Stockholder Agreements, the Registration Rights Agreements with the other
Committed Stockholders, the Registration Statement and the Rights Plan
Amendment.

         (c)      The Participating Purchaser hereby represents and warrants to
the Company as follows as of the date hereof:

                  (i)      the Participating Purchaser has been duly organized
and is validly existing as a limited liability company in good standing under
the laws of the State of Delaware and it has all requisite corporate power and
authority to enter into this Agreement and to consummate the transactions set
forth in this Agreement;

                  (ii)     the execution and delivery by it of this Agreement,
and the consummation by it of the transactions set forth in this Agreement,
have been duly authorized by all necessary action on its part;

                  (iii)    this Agreement has been duly executed and delivered
by it and constitutes a valid and binding obligation of it enforceable against
it in accordance with its terms;

                  (iv)     no authorization, filing, approval or consent of any
governmental authority is necessary to be obtained or made by the Participating
Purchaser in connection with the exercise of the Basic Subscription Privilege,
including without limitation as may be required under the HSR Act, other than
any authorization, filing, approval or consent where the failure to obtain or
make would not have a material adverse effect on the ability of the
Participating Purchaser to comply with its obligations hereunder;

                  (v)      the execution and delivery of this Agreement by it
and the consummation by it of the transactions set forth in this Agreement does
not conflict with, or result in a breach of, any law or regulation of any
governmental authority applicable to it, which conflict or breach would have a
material adverse effect on the ability of the Participating Purchaser to comply
with its obligations hereunder, or any material agreement to which it is a
party, which conflict or breach would have a material adverse effect on the
ability of the Participating Purchaser to comply with its obligations
hereunder;

                  (vi)     it will cause the Accounts to acquire the Commitment
Securities for their own accounts and not with a view to distribution or resale
in any manner which would be in violation of the Securities Act;

                  (vii)    the Participating Purchaser understands that the
Commitment Securities may not be sold unless such disposition is registered
under the Securities Act and applicable state securities laws or is exempt from
registration thereunder;


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                  (viii)   the Participating Purchaser further understands that
the exemption from registration afforded by Rule 144 under the Securities Act
depends on the satisfaction of various conditions, and that, if applicable,
Rule 144 may afford the basis for sales only in limited amounts;

                  (ix)     the Participating Purchaser (and each investor in
the Accounts) is an "accredited investor" (as defined in Rule 501(a) under the
Securities Act) and the Participating Purchaser is a "qualified institutional
buyer" (as defined in Rule 144A of the Securities Act);

                  (x)      as of the date hereof, the Participating Purchaser
beneficially owns (as such term is defined in Section 13 of the Exchange Act)
shares of Common Stock in the amounts shown on Schedule G;

                  (xi)     the Participating Purchaser has investment
discretion over the Rights to be issued to the Accounts and may exercise the
Rights and behalf of the Accounts; the Participating Purchaser has furnished to
the Company for use in the Prospectus the number of shares beneficially owned
by the Accounts in the table under the caption "Principal Stockholders" and the
information provided in footnote 3 to such table; and

                  (xii)    there are no agreements between and among the
Participating Purchaser and any other person (other than its affiliates) for
the purpose of acquiring, holding, voting or disposing of any securities of the
Company, except as described in the Registration Statement.

         Section 4.  Covenants; Legend.

(a)      The Company hereby agrees with the Participating Purchaser that it
will:

         (i)      comply with each of the Specified Covenants in favor of the
Underwriters;

         (ii)     use its reasonable best efforts to cause the Registration
Statement to be declared effective by the Commission as soon as reasonably
practicable;

         (iii)    without limiting the provisions of Section 4(b), not amend,
in any material respect which would be adverse to the Participating Purchaser,
the Basic Subscription Privilege or the Over-Subscription Privilege; and

         (iv)     provide the Participating Purchaser with an opportunity to
review those sections of any proposed press release which relate to the
Participating Purchaser's commitment under this Agreement a reasonable time in
advance of release thereof and, to the extent consistent with applicable law,
to make those amendments to such sections of such press release as may be
reasonably requested by the Participating Purchaser; provided, that it is
understood that the use of the names of parties to this Agreement, the number
and percentage of shares of Common Stock to be acquired by Huff and its
affiliates under this Agreement, the percentage beneficial ownership by Huff of
Common Stock before and/or after the Exercise Date and other general references
to this Agreement are deemed satisfactory to Huff.


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         (b)      Concurrently herewith, the Company is entering into an
Underwriting Agreement. The Company agrees that without the prior written
consent of the Participating Purchaser it will not amend the formula for
determining the exercise price of the Rights or the Purchase Price paid by the
Underwriters, and will not amend any provisions of the Underwriting Agreement
(as in effect on the date hereof) or the Registration Statement ((including the
Prospectus forming a part thereof) in the form filed with the Commission on the
date hereof) which amendment (if effected) would be materially adverse to the
Participating Purchaser's or the Accounts' obligations or rights hereunder.

         (c)      Concurrently herewith, the Participating Purchaser on behalf
of the Accounts is entering into a lock-up agreement with the Underwriters in
the form attached on Schedule B. The Participating Purchaser agrees that, prior
to and including the date which is 7 days after the Closing Date (or if there
is no Closing Date, the Determination Time (as defined in the Underwriting
Agreement)), it and its subsidiaries and affiliates (other than the Company and
its subsidiaries) shall not, without the prior written consent of the Company,
in any manner sell, transfer or otherwise dispose of, agree to sell, transfer
or otherwise dispose of or make any proposal to sell, transfer or otherwise
dispose of, directly or indirectly (through derivatives or otherwise), any
Common Stock or Rights to any person or entity (other than the Company),
including without limitation any short sales of the Common Stock; provided that
the Participating Purchaser or the Accounts may transfer Rights in connection
with a Permitted Rights Transfer. The term "Permitted Rights Transfer" means a
transfer of Rights to an entity as to which the Participating Purchaser
exercises at the time of the transfer exclusive control over the power of such
entity to dispose of the Rights or the underlying Subscription Shares (or which
is otherwise an affiliate or related party of such Participating Purchaser or
managed account for which the Participating Purchaser acts as investment
adviser), provided that (i) the entity agrees with the Company that it will
exercise the Rights transferred to it and (ii) the Participating Purchaser
provides advance written notice of any such transfer to the Company, together
with evidence reasonably satisfactory to the Company of such affiliation,
related party or managed account status or that Participating Purchaser does
have such control, a covenant to cause such transferee to exercise the Rights
so transferred in accordance with the terms of this Agreement and such other
covenants or undertakings to the reasonable satisfaction of the Company that
the terms of this Agreement will be complied with by such entity and the
Participating Purchaser. Any such Permitted Rights Transfer shall not relieve
the Participating Purchaser of any of its obligations under this Agreement.

         (d)      Concurrently herewith, the Company is entering into
participating purchaser agreements with other Committed Stockholders on terms
substantially similar to the terms hereof (together with this Agreement, the
"Committed Stockholder Agreements"). The Company agrees that it will not amend
the Committed Stockholder Agreements unless a substantially similar amendment
(taking into account relative proportionality as among the Committed
Stockholders with respect to economic terms) is made hereunder, with the prior
written consent of the Participating Purchaser (such consent not to be
unreasonably withheld).

         (e)      The Participating Purchaser acknowledges and agrees that each
certificate representing shares of Commitment Securities issued to the
Participating Purchaser upon exercise of the Rights shall bear a legend
containing the following words (and shall make a substantially equivalent
legend or notation on DTC or other electronic trading system):

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. THE
                  SECURITIES HAVE BEEN


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                  ACQUIRED FOR INVESTMENT AND MAY NOT BE SOLD, TRANSFERRED OR
                  OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH SUCH ACT."

The requirement that the foregoing legend be placed upon certificates
evidencing any such securities (and any such legend or notation on DTC or other
electronic trading system) shall cease and terminate upon the earliest of the
following events: (i) when such shares are transferred in a registered public
offering under the Securities Act, (ii) when such shares are transferred
pursuant to Rule 144 under the Securities Act or (iii) when such shares are
transferred in any other transaction if, in the case of (ii) or (iii), the
Participating Purchaser delivers to the Company an opinion of its counsel,
which counsel and opinion shall be reasonably satisfactory to the Company, or a
"no-action" letter from the staff of the Commission, in either case to the
effect that such legend is no longer necessary in order to protect the Company
against a violation by it of the Securities Act upon any sale or other
disposition of such shares without registration thereunder. Upon the occurrence
of any event requiring the removal of a legend hereunder, the Company, upon the
surrender of certificates containing such legend, shall, at its own expense,
deliver to the holder of any such shares as to which the requirement for such
legend shall have terminated, one or more new certificates evidencing such
shares not bearing such legend.

         Section 5.  Conditions.

         (a)      The obligation of the Participating Purchaser to perform its
obligations under Section 2 is subject to the satisfaction or waiver of the
following conditions:

                  (i)      each of the representations and warranties of the
         Company contained in Section 3(b) shall be true and correct at and as
         of the Exercise Date in all material respects;

                  (ii)     the Company shall have complied in all material
         respects with its covenants in this Agreement as of the Exercise Date;

                  (iii)    each of the representations and warranties of the
         Company contained in Section 3(a) shall be true and correct at and as
         of the Exercise Date in all material respects;

                  (iv)     each of the Specified Conditions shall be satisfied
         as of the Exercise Date;

                  (v)      neither the Company nor any Committed Stockholder
         shall have terminated the Participating Purchaser Agreement between
         the Company and such Committed Stockholder.

         (b)      The obligation of the Company to perform its obligations at
the Exercise Date is subject to the satisfaction or waiver of the following
condition:

         (i)      each of the representations and warranties of the
         Participating Purchaser contained herein shall be true and correct at
         and as of the Exercise Date in all material respects.

         (c)      If the Company terminates the Rights Offering prior to the
exercise of the Rights by the Participating Purchaser under Section 2, this
Agreement shall terminate as provided by Section 7 and the Participating
Purchaser will not be required to comply with Section 2.


                                      10
<PAGE>

         Section 6.  Indemnification; Contribution.

         (a)      The Company will indemnify and hold harmless each of the
Participating Purchaser, the Accounts and their affiliates and all of their
respective directors, officers, members, partners, employees, fiduciaries,
agents and each other person who controls such persons within the meaning of
the Securities Act or the Exchange Act (collectively, the "Indemnified
Parties") against any losses, claims, damages or liabilities, joint or several
(including without limitation reasonable attorneys' fees and any and all
expenses whatsoever incurred in investigating, preparing, compromising or
defending against any Third Party Claim, and any and all amounts paid in
settlement of any Third Party Claim), to which such Indemnified Party may
become subject as a result of a Third Party Claim against such Indemnified
Party, under the Securities Act or otherwise, including without limitation as
such losses, claims, damages or liabilities as may arise out of or are based
upon (i) an untrue statement or alleged untrue statement of a material fact
contained in any Preliminary Prospectus, the Registration Statement or the
Prospectus, or any amendment or supplement thereto, or (ii) the omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, and will reimburse
the Indemnified Party for any legal or other expenses reasonably incurred by
such Indemnified Party in connection with investigating or defending any such
Third Party Claim as such expenses are incurred; provided, however, that the
Company shall not be liable in any such case to the extent that any such loss,
claim, damage or liability arises out of or is based upon an untrue statement
or alleged untrue statement or omission or alleged omission made in any
Preliminary Prospectus, the Registration Statement or the Prospectus or any
such amendment or supplement in reliance upon and in conformity with written
information furnished to the Company by the Participating Purchaser expressly
for use therein (including without limitation the matters identified in Section
3(c)(xi) ("Participating Purchaser Information").

         (b)      The Participating Purchaser will indemnify and hold harmless
the Company, its affiliates, and their respective directors, officers, members,
partners, employees, fiduciaries, agents and each other person who controls
such persons within the meaning of the Securities Act or the Exchange Act
against any losses, claims, damages or liabilities (including without
limitation reasonable attorneys' fees and any and all expenses), to which the
Company may become subject, under the Act or otherwise, insofar as such losses,
claims, damages or liabilities arise out of or are based upon an untrue
statement or alleged untrue statement of a material fact contained in any
Preliminary Prospectus, the Registration Statement or the Prospectus, or any
amendment or supplement thereto, or arise out of or are based upon the omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, in each
case to the extent, but only to the extent, that such untrue statement or
alleged untrue statement or omission or alleged omission was made in any
Preliminary Prospectus, the Registration Statement or the Prospectus or any
such amendment or supplement in reliance upon and in conformity with the
Participating Purchaser Information and will reimburse the Company for any
legal or other expenses reasonably incurred by the Company in investigating or
defending any such action or claim as such expenses are incurred.

         (c)      Promptly after receipt by an indemnified party under
paragraph (a) or (b) above of notice of the commencement of any action, such
indemnified party shall, if a claim in respect thereof is to be made against
the indemnifying party under such paragraph, notify the indemnifying party in
writing of the commencement thereof; provided, that the omission so to notify
the indemnifying party shall not relieve it from any liability that it may have
under paragraph (a) or (b) except to the extent it has been materially
prejudiced (through the forfeiture of substantive rights or defenses) by such
failure and, provided further, that the failure to notify the indemnifying
person shall not relieve


                                      11
<PAGE>

it from any liability which it may have to any indemnified party otherwise than
under such paragraph. In case any such action shall be brought against any
indemnified party and it shall notify the indemnifying party of the
commencement thereof, the indemnifying party shall be entitled to participate
therein and, to the extent that it shall wish, jointly with any other
indemnifying party similarly notified, to assume the defense thereof, with
counsel satisfactory to such indemnified party (who shall not, except with the
consent of the indemnified party, be counsel to the indemnifying party), and,
after notice from the indemnifying party to such indemnified party of its
election so to assume the defense thereof, the indemnifying party shall not be
liable to such indemnified party under such paragraph for any legal expenses of
other counsel or any other expenses, in each case subsequently incurred by such
indemnified party, in connection with the defense thereof other than reasonable
costs of investigation. No indemnifying party shall, without the written
consent of the indemnified party, effect the settlement or compromise of, or
consent to the entry of any judgment with respect to, any pending or threatened
action or claim in respect of which indemnification or contribution may be
sought hereunder (whether or not the indemnified party is an actual or
potential party to such action or claim) unless such settlement, compromise or
judgment (i) includes an unconditional release of the indemnified party from
all liability arising out of such action or claim and (ii) does not include a
statement as to or an admission of fault, culpability or a failure to act, by
or on behalf of any indemnified party.

         (d)      If the indemnification provided for in this Section 6 is
unavailable to or insufficient to hold harmless an indemnified party under
paragraph (a) or (b) above in respect of any losses, claims, damages or
liabilities (or actions in respect thereof) referred to therein, then each
indemnifying party shall contribute to the amount paid or payable by such
indemnified party as a result of such losses, claims, damages or liabilities
(or actions in respect thereof) in such proportion as is appropriate to reflect
the relative benefits received by the Company on the one hand and the
Participating Purchaser on the other from the offering of the Rights and
Subscription Shares. If, however, the allocation provided by the immediately
preceding sentence is not permitted by applicable law or if the indemnified
party failed to give the notice required under paragraph (c) above, then each
indemnifying party shall contribute to such amount paid or payable by such
indemnified party in such proportion as is appropriate to reflect not only such
relative benefits but also the relative fault of the Company on the one hand
and the Participating Purchaser on the other in connection with the statements
or omissions which resulted in such losses, claims, damages or liabilities (or
actions in respect thereof), as well as any other relevant equitable
considerations. The relative benefits received by the Company on the one hand
and the Participating Purchaser on the other shall be deemed to be in the same
proportion as the total net proceeds from the Rights Offering (before deducting
expenses) received by the Company bear to the Commitment Fee received by the
Participating Purchaser. The relative fault shall be determined by reference
to, among other things, whether the untrue or alleged untrue statement of a
material fact or the omission or alleged omission to state a material fact
relates to information supplied by the Company on the one hand or the
Participating Purchaser on the other and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission. The Company and the Participating Purchaser agree that
it would not be just and equitable if contributions pursuant to this paragraph
(d) were determined by pro rata allocation or by any other method of allocation
which does not take account of the equitable considerations referred to above
in this paragraph (d). The amount paid or payable by an indemnified party as a
result of the losses, claims, damages or liabilities (or actions in respect
thereof) referred to above in this paragraph (d) shall be deemed to include any
legal or other expenses reasonably incurred by such indemnified party in
connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this paragraph (d), the Participating
Purchaser shall not be required to contribute any amount in excess of the
amount by which the total


                                      12
<PAGE>

price at which the Commitment Securities purchased by it exceed the amount of
any damages which such Participating Purchaser has otherwise been required to
pay by reason of such untrue or alleged untrue statement or omission or alleged
omission. No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Act) shall be entitled to contribution from any person
who was not guilty of such fraudulent misrepresentation.

         (e)      The obligations of the Company under this Section 6 shall be
in addition to any liability which the Company may otherwise have and shall
extend, upon the same terms and conditions, to each person, if any, who
controls such Participating Purchaser within the meaning of the Securities Act
or Exchange Act; and the obligations of the Participating Purchaser under this
Section 6 shall be in addition to any liability which the Participating
Purchaser may otherwise have and shall extend, upon the same terms and
conditions, to each officer and director of the Company and to each person, if
any, who controls the Company within the meaning of the Securities Act or
Exchange Act.

         Section 7.  Termination. This Agreement may be terminated;

                  (i)      at any time prior to the Expiration Date by joint
         written agreement of the Company and the Participating Purchaser;

                  (ii)     at any time by the Company upon its abandonment or
         termination of the Rights Offering;

                  (iii)    by the Company at any time prior to the Effective
         Date;

                  (iv)     by the Participating Purchaser if on the Effective
         Date, the Total Rights Offering Size is equal to or greater than $1.20
         billion;

                  (v)      provided that the Participating Purchaser is not
         then in breach (in any material respect) of this Agreement, by the
         Participating Purchaser if the Effective Date has not occurred by the
         date which is eight weeks following the date of this Agreement
         (provided that if, at least one business day prior to such date and
         any extension of such date, the Company ---------- notifies the
         Participating Purchaser in writing that it wishes to extend such date
         for a consecutive period of not less than one week, and subject to the
         proviso below, not more than three weeks, then the Participating
         Purchaser may not terminate pursuant to this clause (v) for such
         further period provided further that the total period of any such
         extension or -------- ------- extensions shall not exceed three
         additional consecutive weeks; in the event of any extension hereunder,
         the Company shall pay an Extension Fee for each week or part thereof
         that this Agreement is so extended, such fee to be payable as of the
         earlier of (A) five business days after the Exercise Date or (B) five
         business days after the end of such extension period (taking into
         account all such extensions);

                  (vi)     by either party if the Registration Statement has
         been withdrawn from the Commission; or

                  (vii)    by either party if the Underwriters terminate the
         Underwriting Agreement.

A party shall effect any termination under clauses (ii) - (vii) by giving
written notice thereof to the other party.


                                      13
<PAGE>

         Section 8.  Notices. Any notice required to be given hereunder shall
be sufficient if in writing, and sent by courier service (with proof of
service), hand delivery or certified or registered mail (return receipt
requested and first-class postage prepaid), addressed as follows:

         If to the Company, to:

                  NTL Incorporated
                  110 East 59th Street, 26th Floor
                  New York, New York  10022
                  Attention:  Scott Schubert

         with a copy to:

                  NTL Incorporated
                  NTL House
                  Bartley Wood Business Park
                  Bartley Way, Hook
                  Hampshire  R627 9UP
                  Attention:  Robert MacKenzie

         with a copy to:

                  Fried, Frank, Harris, Shriver & Jacobson
                  One New York Plaza
                  New York, NY  10004
                  Attention:  Bryan Hall; Jeffrey Bagner

         If to Participating Purchaser, to:

                  W.R. Huff Asset Management Co., L.L.C.
                  1776 On the Green
                  67 Park Place
                  Morristown, New Jersey  07960
                  Attn:  Joseph Thornton

or to such other address as any party shall specify by written notice so given,
and such notice shall be deemed to have been delivered as of the date so
personally delivered or mailed.

         Section 9.  Expenses. The Company agrees to reimburse the
Participating Purchaser for its reasonable out-of-pocket legal expenses
incurred in connection with the preparation and negotiation of this Agreement
and the Registration Rights Agreement and related matters, subject to
presentation of invoices in reasonable detail and provided that such reimbursed
expenses shall not exceed $150,000. Such reimbursements shall be payable after
the Exercise Date or termination hereof and reasonably promptly after the
submission of the invoices therefor.

         Section 10.  Existing Registration Rights Agreement. With respect to
the registration under the Securities Act by the Company of the Rights and the
shares of its Common Stock to be issued to persons exercising such Rights or to
any Underwriter, the Participating Purchaser hereby


                                      14
<PAGE>

(1) waives all rights (if any) to prior notice under Section 3.2 of the
Existing Registration Rights Agreement, (ii) agrees that it will not exercise
all rights (if any) under Section 3.1 or Section 3.2 of the Existing
Registration Rights Agreement and (iii) if proposed by the Company, agrees to
execute an amendment to the Existing Registration Rights Agreement providing
clarification that the incidental registration rights under Section 3.2 do not
apply to public registered rights offering transactions.

         Section 11.  Assignment; No Third Party Beneficiaries. This Agreement
may not be assigned; except that the Participating Purchaser may assign its
obligations to exercise Rights in connection with a Permitted Rights Transfer
to the transferee thereof provided that such transferee agrees to be bound by
the provisions of this Agreement and, notwithstanding such assignment, the
Participating Purchaser shall remain liable for its obligations under this
Agreement. This Agreement shall inure to the benefit of and be binding upon the
Participating Purchaser, the Company and their respective successors. Nothing
expressed or mentioned in this Agreement is intended or shall be construed to
give any person, other than Participating Purchaser, the Company and their
respective successors or permitted assigns, or any person specified in Section
6 any legal or equitable right, remedy or claim under or in respect of this
Agreement or any provision herein contained. This Agreement and all conditions
and provisions hereof are intended to be for the sole and exclusive benefit of
Participating Purchaser, the Company and their respective successors and
permitted assigns and persons specified in Section 6 and for the benefit of no
other person.

         Section 12.  Specific Performance. The parties agree that irreparable
damage will result in the event that this Agreement is not specifically
enforced, and the parties agree that any damages available at law for a breach
of this Agreement would not be an adequate remedy. Therefore, the provisions of
this Agreement and the obligations of the parties under this Agreement shall be
enforceable in a court of equity, or other tribunal with jurisdiction by a
decree of specific performance, and appropriate injunctive relief may be
applied for and granted in connection therewith. Such remedies shall, however,
be cumulative and not exclusive and shall be in addition to any other remedies
which a party may have under this Agreement or otherwise.

         Section 13.  Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York.

         Section 14.  Consent to Jurisdiction; Waiver of Jury Trial. (a) Each
party to this Agreement irrevocably submits to the non-exclusive jurisdiction
of (i) the state courts of the State of New York, New York County, and (ii) the
United States District Court for the Southern District of New York, for the
purposes of any suit, action or other proceeding arising out of this Agreement
or any transactions contemplated hereby. Each of the parties, for itself and in
connection with its properties, generally and unconditionally, waives any
defense of forum non conveniens, and irrevocably agrees to be bound by any
judgment rendered in connection with this Agreement.

         (b)      Each of the parties to this Agreement hereby waives its
respective rights to a jury trial of any claim or cause of action based upon or
arising out of this Agreement. The scope of this waiver is intended to be
all-encompassing of any and all disputes that may be filed in any court and
that relate to the subject matter of this agreement, including without
limitation contract claims, tort claims, breach of duty claims, and all other
common law and statutory claims.


                                      15
<PAGE>

         Section 15.  Amendment; Waivers. This Agreement may not be amended or
modified (nor may the terms be waived) by the parties unless such amendment,
modification or waiver is in writing signed by the Company and the
Participating Purchaser.

         Section 16.  Survival. All representations and warranties of the
Company contained herein shall not survive the termination hereof or the
closing date of the transactions contemplated hereby.

         Section 17.  Interpretation. The term "including" means "including
without limitation". The captions and headings are for convenience of reference
only and shall not in any way affect the meaning or interpretation of this
Agreement. All Section and Schedule references refer to Sections and Schedules
to this Agreement, unless expressly stated otherwise

         Please sign and return to the Company a counterpart hereof, whereupon
this instrument, along with all counterparts, will become a binding agreement
between the Participating Purchaser and the Company in accordance with its
terms.


                                      16
<PAGE>

                                          Very truly yours,


                                          NTL INCORPORATED




                                          By:  /s/ Scott E. Schubert
                                               ------------------------------
                                               Name:  Scott E. Schubert
                                               Title: Chief Financial Officer

Accepted as of the date first above written.

W.R. Huff Asset Management Co., L.L.C.




By:  /s/ Edwin M. Banks
     ------------------------
     Name:  Edwin M. Banks
     Title: Portfolio Manager

[Signature Page to Participating Purchaser Agreement]


<PAGE>

                                                                     SCHEDULE A

                        [Form of Underwriting Agreement]


<PAGE>

                                                                     SCHEDULE B

                          [Form of Lock-up Agreement]


<PAGE>

                                                                     SCHEDULE C

                              SPECIFIED CONDITIONS

The following conditions set forth in the Underwriting Agreement constitute
"Specified Conditions" under this Agreement:

1.       Section 7(b)(i) [Effectiveness of Registration Statement]

2.       Section 7(b)(ii) [Listing of Rights and Allotted Shares]

3.       Section 7(b) (ix) [No Injunction]

Note: the captions provided in brackets are for convenience of reference only
and do not affect the meaning or interpretation of the representation and
warranty.


<PAGE>

                                                                     SCHEDULE D

                              SPECIFIED COVENANTS

The following covenants set forth in the Underwriting Agreement in favor of the
Underwriters constitute "Specified Covenants" under this Agreement (as modified
hereon):

1.       Section 5(a) [Review of Registration Statement];provided however that

(i)      references to the "Shares" shall mean the Commitment Securities;

(ii)     references to the Underwriters and the Lead Underwriters shall mean
instead the Participating Purchaser;

(iii)    after the words, "with an opportunity to review any proposed amendment
or supplement to the Initial Registration Statement, any Preliminary Prospectus
or Prospectus" the following words shall be inserted, "where the amendment or
supplement relates to the Participating Purchaser Agreement or the transactions
contemplated by the Participating Purchaser Agreement"; and

(iv)     After the words, "to make no amendments or any supplements to the
Initial Registration Statement, any Preliminary Prospectus or Prospectus," the
following words shall be inserted, "relating to the Participating Purchaser
Agreement or the transactions contemplated by the Participating Purchaser
Agreement"

2.       Section 5(e) [Earnings Statement]

3.       Section 5(h) [Use of Proceeds]

Note: the captions provided in brackets are for convenience of reference only
and do not affect the meaning or interpretation of the representation and
warranty.


<PAGE>

                                                                     SCHEDULE E

                    SPECIFIED REPRESENTATIONS AND WARRANTIES

         The following representations and warranties set forth in the
Underwriting Agreement constitute "Specified Representations and Warranties"
under this Agreement (as modified hereon):

1.       Section 1(a) [Registration Statement]

2.       Section 1(b) [Registration Statement]; provided however that at the
         end of such representation and warranty the following shall be added:

                  ; provided, however that this representation and warranty
                  shall not apply to any statements or omissions made in
                  reliance upon and in conformity with information furnished in
                  writing to the Company by the Participating Purchaser
                  expressly for use therein.

3.       Section 1(c) [Certain Events]

4.       Section 1(d) [Real Property]

5.       Section 1(f) [Capitalization]

6.       Section 1(g) [Issuance of Rights]

7.       Section 1(i) [Consents and Filings]

8.       Section 1(j) [Charter and by-laws]

9.       Section 1(k) [Certain Statements]

10.      Section 1(l) [Legal Proceedings]

11.      Section 1(m) [Investment Company Acts]

12.      Section 1(n) [Accountants]

13.      Section 1(o) [Intellectual Property]

14.      Section (p) [Labor Disputes]

15.      Section 1(q)(i) [Tax]

16.      Section 1(r) [Permits, etc.]

17.      Section 1(s) [Insurance]

18.      Section 1(t) [Environmental Laws]

19.      Section 1(u) [Financial Statements]

20.      Section 1(v) [Controls]


<PAGE>

21.      Section 1(w) [Nasdaq]

22.      Section 1(x) [Sarbanes-Oxley]

Notes: the captions provided in brackets are for convenience of reference only
and do not affect the meaning or interpretation of the representation and
warranty.


<PAGE>

                                                                     SCHEDULE F

                        Commitment Fee and Extension Fee

The Commitment Fee to be paid by the Company to the Participating Purchaser
will be an amount equal to (x) the Applicable Percentage (defined below) times
(y) the dollar amount that is equal to the aggregate exercise price of the
Basic Subscription Privileges for all of the Rights issued to the Accounts in
the Rights Offering so exercised by the Accounts as required by the terms of
this Agreement (the "Committed Aggregate Exercise Price"); provided that the
minimum Commitment Fee payable upon exercise of the Rights in accordance
herewith shall be 0.02125 times $136,500,000.

         The term "Applicable Percentage" means a percentage, expressed as a
decimal, equal to (A) the Underwriting Fee percentages (expressed as a decimal)
applicable to the Rights Offering transaction under the terms of the
Underwriting Agreement (as set forth on Schedule II thereto) less (B) 0.00375,
as follows:


           Underwriting Fee Percentage                  Applicable Percentage

                     .02500                                    .02125

                     .02625                                    .02250

                     .02750                                    .02375

                     .02875                                    .02500

                     .03000                                    .02625

         The term "Total Rights Offering Size" means the aggregate exercise
price of the Basic Subscription Privileges for all of the Rights issued in the
Rights Offering to all persons.

         The term "Extension Fee" as used in Section 7 means a fee equal to
0.00125 of the Committed Aggregate Exercise Price payable for each week or part
thereof that the Agreement is extended under Section 7.

         Notwithstanding anything to the contrary herein, fees shall only be
payable with respect to Rights issued on behalf of the shares of Common Stock
beneficially owned by Huff on the date hereof, as shown on Schedule G.


<PAGE>

                                                                     SCHEDULE F

                          Beneficial Ownership by Huff

         Huff has beneficial ownership as of the date hereof, of 6,613,995
shares of Common Stock.