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                                                                    Exhibit 4.18
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                                  $600,000,000
                   7% CONVERTIBLE SUBORDINATED NOTES DUE 2008
                          REGISTRATION RIGHTS AGREEMENT

                          Dated as of December 16, 1998

                                  by and among

                                NTL INCORPORATED

                                       and

               DONALDSON, LUFKIN & JENRETTE SECURITIES CORPORATION
                        MORGAN STANLEY & CO. INCORPORATED
                              GOLDMAN, SACHS & CO.
                           BT ALEX. BROWN INCORPORATED
                              CHASE SECURITIES INC.
                            SALOMON SMITH BARNEY INC.
                             WARBURG DILLON READ LLC

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      This Registration Rights Agreement (this "Agreement") is made and entered
into as of December 16, 1998 by and among NTL Incorporated, a Delaware
corporation (the "Company"), and Donaldson, Lufkin & Jenrette Securities
Corporation, Morgan Stanley & Co. Incorporated, Chase Securities, Inc., Goldman,
Sachs & Co., BT Alex. Brown Incorporated, Salomon Smith Barney Inc, and Warburg,
Dillon Read LLC (each an "Initial Purchaser" and collectively, the "Initial
Purchasers"). The Company proposes to issue and sell to the Initial Purchasers
(the "Initial Placement") $600,000,000 principal amount of its 7% Convertible
Subordinated Notes due 2008 (the "Notes"). As an inducement to the Initial
Purchasers to enter into the purchase agreement, dated as of December 10, 1998
(the "Purchase Agreement"), and in satisfaction of a condition to the Initial
Purchasers' obligations thereunder, the Company agrees with the Initial
Purchasers, (i) for the benefit of the Initial Purchasers and (ii) for the
benefit of the holders from time to time of the Notes whose names appear in the
register maintained by the Registrar in accordance with the provisions of the
Indenture (as defined in Section 1 hereof) (including the Initial Purchasers),
as follows:

SECTION 1. DEFINITIONS

      Capitalized terms used herein without definition shall have their
respective meanings set forth in the Purchase Agreement. As used in this
Agreement, the following capitalized defined terms shall have the following
meanings:

      "Act" means the Securities Act of 1933, as amended, and the rules and
regulations of the Commission promulgated thereunder.

      "Affiliate" of any specified person means any other person which, directly
or indirectly, is in control of, is controlled by, or is under common control
with, such specified person. For purposes of this definition, control of a
person means the power, direct or indirect, to direct or cause the direction of
the management and policies of such person whether by contract or otherwise; and
the terms "controlling" and "controlled" have meanings correlative to the
foregoing.

      "Agreement" menas this Registration Rights Agreement.

      "Closing Date" has the meaning set forth in the Purchase Agreement.

      "Commission" means the Securities and Exchange Commission.

      "Common Stock" means the common stock of the Company, par value $0.01 per
share, issuable upon the conversion of the Notes.

      "Company" means NTL Incorporated.

      "Exchange Act" means the Securities Exchange Act of 1934, as amended, and
the rules and regulations of the Commission promulgated thereunder.

      "Holder" has the meaning set forth in Section 2 hereof.

      "Indenture" means the Indenture, dated as of December 16, 1998, between
the Company and the Trustee, relating to the Notes, as the same may be amended
from time to time in accordance with the terms thereof.

      "Initial Placement" has the meaning set forth in the preamble hereto.
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      "Initial Purchasers" means, collectively, Donaldson, Lufkin & Jenrette
Securities Corporation, Morgan Stanley & Co. Incorporated, Chase Securities,
Inc., Goldman, Sachs & Co., BT Alex. Brown Incorporated, Salomon Smith Barney
Inc., and Warburg, Dillon Read LLC.

      "Losses" has the meaning set forth in Section 7(d) hereof.

      "Majority Holders" means the Holders of a majority of the aggregate
principal amount of securities registered under a Shelf Registration Statement.

      "Notes" has the meaning set forth in the preamble hereto.

      "Prospectus" means the prospectus included in any Shelf Registration
Statement (including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A under the Act), as amended or
supplemented by any prospectus supplement, with respect to the terms of the
offering of any portion of Transfer Restricted Securities covered by such Shelf
Registration Statement, and all amendments and supplements to the Prospectus,
including post-effective amendments.

      "Shelf Registration" means a registration effected pursuant to Section 3
hereof.

      "Shelf Registration Period" has the meaning set forth in Section 3(b)
hereof.

      "Shelf Registration Statement" means a "shelf" registration statement of
the Company pursuant to the provisions of Section 3 hereof that covers some or
all of the Transfer Restricted Securities as applicable, on an appropriate form
under Rule 415 under the Act, or any similar rule that may be adopted by the
Commission, amendments and supplements to such registration statement, including
post-effective amendments, and in each case, including the Prospectus contained
therein, all exhibits thereto and all material incorporated by reference
therein.

      "Supplement Delay Period" means any period commencing on the date of
receipt by a Holder of Transfer Restricted Securities of any notice from the
Company of the existence of any fact or event of the kind described in Section
4(b)(2) hereof and ending on the date of receipt by such Holder of an amended or
supplemented Shelf Registration Statement or Prospectus, as contemplated by
Section 4(h) hereof, or the receipt by such Holder of written notice from the
Company (the "Advice") that the use of the Prospectus may be resumed, and the
receipt of copies of any additional or supplemental filings that are
incorporated by reference in the Prospectus.

      "Transfer Restricted Securities" means each Note and the Common Stock
issuable upon conversion thereof until (i) the date on which such Note or the
Common Stock issuable upon conversion thereof has been effectively registered
under the Act and disposed of in accordance with the Shelf Registration
Statement, (ii) the date on which such Note or Common Stock issuable upon
conversion thereof is distributed to the public pursuant to Rule 144 under the
Act (or any similar provision then in effect) or is saleable pursuant to Rule
144(k) under the Act or (iii) the date on which such Note is converted into
Common Stock in accordance with the terms and provisions of the Indenture or
otherwise ceases to be outstanding.

      "Trustee" means the trustee with respect to the Notes under the Indenture.

      "underwriter" means any underwriter of Notes in connection with an
offering thereof under a Shelf Registration Statement.


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<PAGE>   4

SECTION 2. HOLDERS

      A person is deemed to be a holder of Transfer Restricted Securities (each,
a "Holder") whenever such person becomes the registered holder of such Notes
under the Indenture and includes broker-dealers that hold Transfer Restricted
Securities (i) as a result of market making activities and other trading
activities and (ii) which were acquired directly from the Company or an
Affiliate.

SECTION 3. SHELF REGISTRATION

      The Company shall within 90 days of the date of original issuance of the
Notes, file with the Commission and thereafter shall use its best efforts to
cause to be declared effective under the Act on or prior to 180 days (plus any
additional days allowed as a result of a Supplemental Delay Period) after the
date of original issuance of the Notes, a Shelf Registration Statement relating
to the offer and sale of the Transfer Restricted Securities by the Holders from
time to time in accordance with the methods of distribution elected by such
Holders and set forth in such Shelf Registration Statement.

      The Company shall use its best efforts to keep the Shelf Registration
Statement continuously effective in order to permit the Prospectus forming part
thereof to be usable by Holders for a period of two years from the date the
Shelf Registration statement is declared effective by the Commission or such
shorter period that will terminate when (i) all the Transfer Restricted
Securities covered by the Shelf Registration Statement have been sold pursuant
to the Shelf Registration Statement, (ii) the date on which, in the opinion of
counsel to the Company, all of the Transfer Restricted Securities then held by
the Holders may be sold by such Holders in the public United States securities
markets in the absence of a registration statement covering such sales or (iii)
the date on which there ceases to be outstanding any Transfer Restricted
Securities (in any such case, such period being called the "Shelf Registration
Period"). The Company shall be deemed not to have used its best efforts to keep
the Shelf Registration Statement effective during the requisite period if it
voluntarily takes any action that would result in Holders of Transfer Restricted
Securities covered thereby not being able to offer and sell such securities
during that period, unless (i) such action is required by applicable law, (ii)
such action is taken by the Company in good faith and for valid business reasons
(not including avoidance of the Company's obligations hereunder), including the
acquisition or divestiture of assets, so long as the Company promptly thereafter
complies with the requirements of Section 4(h) hereof, if applicable or (iii)
such action is taken because of any fact or circumstance giving rise to a
Supplement Delay Period.

SECTION 4. REGISTRATION PROCEDURES

      In connection with any Shelf Registration Statement, the following
provisions shall apply:

      (a) The Company shall ensure that (i) any Shelf Registration Statement and
any amendment thereto and any Prospectus forming part thereof and any amendment
or supplement thereto complies in all material respects with the Act and the
rules and regulations thereunder, (ii) any Shelf Registration Statement and any
amendment thereto does not, when it becomes effective, contain an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein not misleading and
(iii) any Prospectus forming part of any Shelf Registration Statement, and any
amendment or supplement to such Prospectus, does not include an untrue statement
of a material fact or omit to state a material fact necessary in order to make
the statements, in the light of the circumstances under which they were made,
not misleading.

      (b) (1) The Company shall advise the Initial Purchasers and the Holders of
Transfer Restricted 


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Securities named in any Shelf Registration Statement, and, if requested by the
Initial Purchasers or any such Holder, confirm such advice in writing when a
Shelf Registration Statement and any amendment thereto has been filed with the
Commission and when the Shelf Registration Statement or any post-effective
amendment thereto has become effective.

            (2) The Company shall advise the Initial Purchasers and the Holders
of Transfer Restricted Securities named in any Shelf Registration Statement,
which have provided in writing to the Company a telephone or facsimile number
and address for notices, and, if requested by the Initial Purchasers or any such
Holder, confirm such advice in writing:

            (i) of any request by the Commission for amendments or supplements
      to the Shelf Registration Statement or the Prospectus included therein or
      for additional information;

            (ii) of the initiation by the Commission of proceedings relating to
      a stop order suspending the effectiveness of the Shelf Registration
      Statement;

            (iii) of the issuance by the Commission of any stop order suspending
      the effectiveness of the Shelf Registration Statement;

            (iv) of the receipt by the Company of any notification with respect
      to the suspension of the qualification of the securities included therein
      for sale in any jurisdiction or the initiation or threatening of any
      proceeding for such purpose; and

            (v) of the existence of any fact and the happening of any event
      (including, without limitation, pending negotiations relating to, or the
      consummation of, a transaction or the occurrence of any event which would
      require additional disclosure of material non-public information by the
      Company in the Shelf Registration Statement as to which the Company has a
      bona fide business purpose for preserving confidential or which renders
      the Company unable to comply with Commission requirements) that, in the
      opinion of the Company, makes untrue any statement of a material fact made
      in its Shelf Registration Statement, the Prospectus or any amendment or
      supplement thereto or any document incorporated by reference therein or
      requires the making of any changes in the Shelf Registration Statement or
      the Prospectus so that, as of such date, the statements therein are not
      misleading and do not omit to state a material fact required to be stated
      therein or necessary to make the statements therein (in the case of the
      Prospectus, in light of the circumstances under which they were made) not
      misleading.

      Such advice may be accompanied by an instruction to suspend the use of the
Prospectus until the requisite changes have been made.

      (c) The Company shall use its best efforts to obtain the withdrawal of any
order suspending the effectiveness of any Shelf Registration Statement at the
earliest possible time.

      (d) The Company shall use its best efforts to furnish to each selling
Holder named in any Shelf Registration Statement who so requests in writing and
who has provided to the Company an address for notices, without charge, at least
one conformed copy of such Shelf Registration Statement and any post-effective
amendment thereto, including financial statements and, if the Holder so requests
in writing, all exhibits and schedules (including those incorporated by
reference).

      (e) The Company shall, during the Shelf Registration Period, deliver to
each Holder of Transfer Restricted Securities named in any Shelf Registration
Statement and who has provided to the Company 


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an address for notices, without charge, as many copies of the Prospectus
(including each preliminary Prospectus) contained in such Shelf Registration
Statement and any amendment or supplement thereto as such Holder may reasonably
request; subject to any notice by the Company in accordance with Section 5(b)
hereof, the Company consents to the use of the Prospectus or any amendment or
supplement thereto by each of the selling Holders for the purposes of offering
and resale of the Transfer Restricted Securities covered by the Prospectus in
accordance with the applicable regulations promulgated under the Act.

      (f) Prior to any offering of Transfer Restricted Securities pursuant to
any Shelf Registration Statement, the Company shall register or qualify or
cooperate with the Holders of Transfer Restricted Securities named therein and
their respective counsel in connection with the registration or qualification of
such Transfer Restricted Securities for offer and sale under the securities or
blue sky laws of such jurisdictions of the United States as any such Holders
reasonably request in writing not later than the date that is five business days
prior to the date upon which this Agreement specifies that the Shelf
Registration Statement shall become effective; provided, however, that the
Company will not be required to qualify generally to do business in any
jurisdiction where it is not then so qualified or to take any action which would
subject it to general service of process or to taxation in any such jurisdiction
where it is not then so subject.

      (g) The Company shall endeavor to cooperate with the Holders of Transfer
Restricted Securities to facilitate the timely preparation and delivery of
certificates representing Transfer Restricted Securities to be sold pursuant to
any Shelf Registration Statement free of any restrictive legends and in such
denominations and registered in such names as Holders may request in writing at
least two business days prior to sales of securities pursuant to such Shelf
Registration Statement.

      (h) Upon the occurrence of any event contemplated by paragraph (b)(2)(v)
hereof, the Company shall promptly prepare a post-effective amendment to any
Shelf Registration Statement or an amendment or supplement to the related
Prospectus or file any other required document so that as thereafter delivered
to purchasers of the Transfer Restricted Securities covered thereby, the
Prospectus will not include an untrue statement of a material fact or omit to
state any material fact necessary to make the statements therein, in the light
of the circumstances under which they were made, not misleading; provided that
in the event of a material business transaction (including, without limitation,
pending negotiations relating to such a transaction) which would, in the opinion
of counsel to the Company, require disclosure by the Company in the Shelf
Registration Statement of material non-public information for which the Company
has a bona fide business purpose for not disclosing, then for so long as such
circumstances exist, the Company shall not be required to prepare and file a
supplement or post-effective amendment hereunder.

      (i) Not later than the effective date of any such Shelf Registration
Statement hereunder, the Company shall cause to be provided a CUSIP number for
the Notes registered under such Shelf Registration Statement, and provide the
applicable trustee with printed certificates for such Notes in a form eligible
for deposit with The Depository Trust Company.

      (j) The Company shall use its best efforts to comply with all applicable
rules and regulations of the Commission and shall make generally available to
its security holders in a regular filing on Form 10-Q or 10-K an earnings
statement satisfying the provisions of Rule 158 (which need not be audited) for
the twelve-month period commencing after effectiveness of the Shelf Registration
Statement.

      (k) The Company shall cause the Indenture to be qualified under the Trust
Indenture Act in a timely manner.


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<PAGE>   7

      (l) The Company may require each Holder of Transfer Restricted Securities,
which are to be sold pursuant to any Shelf Registration Statement, to furnish to
the Company within 20 business days after written request for such information
has been made by the Company, such information regarding the Holder and the
distribution of such securities as the Company may from time to time reasonably
require for inclusion in such Shelf Registration Statement and such other
information as may be necessary or advisable in the reasonable opinion of the
Company and its counsel, in connection with such Shelf Registration Statement.
No Holder of Transfer Restricted Securities shall be entitled to the benefit of
any Liquidated Damages (as defined in the Indenture) under the Indenture or be
entitled to use the Prospectus unless and until such Holder shall have furnished
the information required by this Section 4(l) and all such information required
to be disclosed in order to make the information previously furnished to the
Company by such Holder not materially misleading.

      (m) The Company shall, if requested, promptly incorporate in a Prospectus
supplement or post-effective amendment to a Shelf Registration Statement, such
information as the Majority Holders reasonably agree should be included therein
and shall make all required filings of such Prospectus supplement or
post-effective amendment as soon as notified of the matters to be incorporated
in such Prospectus supplement or post-effective amendment; provided, however,
that the Company shall not be required to take any action pursuant to this
Section 4(m) that would, in the opinion of counsel for the Company, violate
applicable law or to include information the disclosure of which at the time
would have an adverse effect on the business or operations of the Company and/or
its subsidiaries, as determined in good faith by the Company.

      (n) The Company shall enter into such agreements and take all other
reasonably appropriate actions in order to expedite or facilitate the
registration or the disposition of the Transfer Restricted Securities, and in
connection therewith, if an underwriting agreement is entered into, cause the
same to contain indemnification provisions and procedures no less favorable than
those set forth in Section 7 (or such other provisions and procedures acceptable
to the Majority Holders), with respect to all parties to be indemnified pursuant
to Section 7 from Holders of Notes to the Company.

      (o) The Company shall upon receipt of a reasonable request in writing
therefor:

            (i) make reasonably available at reasonable times prior to the
      effectiveness of the related Shelf Registration Statement for inspection
      by representatives of the Holders of Transfer Restricted Securities to be
      registered thereunder and any attorney, accountant or other agent retained
      by the Holders, at the office where normally kept during normal business
      hours, all financial and other records, pertinent corporate documents and
      properties of the Company and its subsidiaries, and cause the Company's
      officers, directors and employees to supply all relevant information
      reasonably requested by the Holders attorney, accountant or other agent in
      connection with any such Shelf Registration Statement as is customary for
      similar due diligence examinations; provided, however, that the foregoing
      inspection and information gathering shall be coordinated by one counsel
      designated by the Holders and that such persons shall first agree in
      writing with the Company that any information that is designated in
      writing by the Company, in good faith, as confidential at the time of
      delivery of such information shall be kept confidential by such person,
      unless such disclosure is made in connection with a court proceeding or
      required by law, or such information becomes available to the public
      generally or through a third party without an accompanying obligation of
      confidentiality;

            (ii) obtain opinions of counsel to the Company and updates thereof
      (which counsel and opinions (in form, scope and substance) shall be
      reasonably satisfactory to the Majority Holders), 


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<PAGE>   8

      addressed to each selling Holder covering such matters (in form, scope and
      substance) as those matters set forth in Section 6(a), (b) and (c) of the
      Purchase Agreement;

            (iii) obtain "cold comfort" letters (or, in the case of any person
      that does not satisfy the conditions for receipt of a "cold comfort"
      letter specified in Statement on Auditing Standards No. 72, an
      "agreed-upon procedures letter") and updates thereof from the independent
      certified public accountants of the Company (and, if necessary, any other
      independent certified public accountants of any subsidiary of the Company
      or of any business acquired by the Company for which financial statements
      and financial data are, or are required to be, included in the Shelf
      Registration Statement), addressed where reasonably practicable to each
      selling Holder of Transfer Restricted Securities registered thereunder and
      the underwriters, if any, in customary form and covering matters of the
      type customarily covered in "cold comfort" letters in connection with
      primary underwritten offerings; and

            (iv) deliver such documents and certificates as may be reasonably
      requested by the Majority Holders, including those to evidence compliance
      with Section 4(h).

            The foregoing actions set forth in clauses (ii), (iii), (iv) and (v)
      of this Section 4(o) shall, if reasonably requested by the Majority
      Holder, be performed at (A) the effectiveness of such Shelf Registration
      Statement and each post-effective amendment thereto.

            (v) The Company may offer securities of the Company other than the
      Notes under the Shelf Registration Statement, except where such offer
      would conflict with the terms of the Purchase Agreement.

SECTION 5. HOLDERS' AGREEMENTS

      Each Holder of Transfer Restricted Securities , by the acquisition of such
Transfer Restricted Securities, agrees:

      (a) To furnish the information required to be furnished pursuant to
Section 4(l) hereof within the time period set forth therein.

      (b) That upon receipt of a notice of the commencement of a Supplement
Delay Period, it will keep the fact of such notice confidential, forthwith
discontinue disposition of its Transfer Restricted Securities pursuant to the
Shelf Registration Statement, and will not deliver any Prospectus forming a part
thereof until receipt of the amended or supplemented Shelf Registration
Statement or Prospectus, as applicable, as contemplated by Section 4(h) hereof,
or until receipt of the Advice. If a Supplement Delay Period should occur, the
Shelf Registration Period shall be extended by the number of days of which the
Supplement Delay Period is comprised; provided that the Shelf Registration
Period shall not be extended if the Company has received an opinion of counsel
(which counsel, if different from counsel to the Company referred to in Section
6(b) of the Purchase Agreement, shall be reasonably satisfactory to the Majority
Holders of the Transfer Restricted Securities named in the Shelf Registration
Period) to the effect that the Transfer Restricted Securities can be freely
tradeable without the continued effectiveness of the Shelf Registration
Statement.

      (c) If so directed by the Company in a notice of the commencement of a
Supplement Delay Period, each Holder of Transfer Restricted Securities will
deliver to the Company (at the Company's expense) all copies, other than
permanent file copies then in such Holder's possession, of the Prospectus
covering the 


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Transfer Restricted Securities.

      (d) Sales of such Transfer Restricted Securities pursuant to a Shelf
Registration Statement shall only be made in the manner set forth in such
currently effective Shelf Registration Statement.

SECTION 6. REGISTRATION EXPENSES

      The Company shall bear all expenses incurred in connection with the
performance of its obligations under Sections 3 and 4 hereof and will reimburse
the Holders for the reasonable fees and disbursements of one firm or counsel
designated by the Majority Holders to act as counsel for the Holders in
connection with any Shelf Registration Statement. Notwithstanding the foregoing
or anything in this Agreement to the contrary, each Holder shall pay all
underwriting discounts and commission of any underwriters with respect to any
Transfer Restricted Securities sold by it.

SECTION 7. INDEMNIFICATION AND CONTRIBUTION

      (a) In connection with Shelf Registration Statement, the Company agrees to
indemnify and hold harmless each Holder of Transfer Restricted Securities
covered thereby (including each Initial Purchaser), the directors, officers,
employees, partners, representatives and agents of each such Holder and each
person who controls any such Holder within the meaning of either Section 15 of
the Act or Section 20 of the Exchange Act against any and all losses, claims,
damages or liabilities, joint or several, to which they or any of them may
become subject under the Act, the Exchange Act or other Federal or state
statutory law or regulation, at common law or otherwise, insofar as such losses,
claims, damages or liabilities (or actions in respect thereof) arise out of, or
are based upon, any untrue statement or alleged untrue statement of a material
fact contained in the Shelf Registration Statement as originally filed or in any
amendment thereof, or in any preliminary Prospectus or Prospectus, or in any
amendment thereof 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, and
to reimburse each such indemnified party, as incurred, for any legal or other
expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that (i) the Company will not be liable in any case to the extent that any such
loss, claim, damage or liability arises out of, or is based upon, any such
untrue statement or alleged untrue statement or omission or alleged omission
made therein in reliance upon and in conformity with written information
furnished to the Company by or on behalf of any such Holder specifically for
inclusion therein and (ii) the Company will not be liable to any indemnified
party under this indemnity agreement with respect to the Shelf Registration
Statement or Prospectus to the extent that any such loss, claim, damage or
liability of such indemnified party results solely from an untrue statement of a
material fact contained in, or the omission of a material fact from, the Shelf
Registration Statement or Prospectus, which untrue statement or omission was
corrected in an amended or supplemented Shelf Registration Statement or
Prospectus, if the person alleging such loss, claim, damage or liability was not
sent or given, at or prior to the written confirmation of such sale, a copy of
the amended or supplemented Shelf Registration Statement or Prospectus if the
Company had previously furnished copies thereof to such indemnified party and if
delivery of a prospectus is required by the Act and was not so made. This
indemnity agreement will be in addition to any liability which the Company may
otherwise have.

      (b) Each Holder of Transfer Restricted Securities covered by a Shelf
Registration Statement (including each Initial Purchaser) severally agrees to
indemnify and hold harmless (i) the Company, (ii) each of its directors, (iii)
each of its officers who signs such Shelf Registration Statement and (iv) each
person who controls the Company within the meaning of either the Act or the
Exchange Act to the same 


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extent as the foregoing indemnity from the Company to each such Holder, but only
with reference to written information relating to such Holder furnished to the
Company by or on behalf of such Holder specifically for inclusion in the
documents referred to in the foregoing indemnity. This indemnity agreement will
be in addition to any liability which any such Holder may otherwise have. In no
event shall any Holder, its directors, officers or any person who controls such
Holder be liable or responsible for any amount in excess of the amount by which
the total amount received by such Holder with respect to its sale of Transfer
Restricted Securities pursuant to a Shelf Registration Statement exceeds (i) the
amount paid by such Holder for such Transfer Restricted Securities and (ii) the
amount of any damages that such Holder, its directors, officers or any person
who controls such Holder has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission or alleged omission.

      (c) Promptly after receipt by an indemnified party under this Section 7 or
notice of the commencement of any action, the indemnified party will, if a claim
in respect thereof is to be made against the indemnifying party under this
Section 7, notify the indemnifying party in writing of the commencement thereof;
but the failure to so notify the indemnifying party (i) will not relieve it from
liability under paragraph (a) or (b) above unless and to the extent it did not
otherwise learn of such action and such failure results in the forfeiture by the
indemnifying party of substantial rights and defenses and (ii) will not, in any
event, relieve the indemnifying party from any obligations to any indemnified
party other than the indemnification obligation provided in paragraph (a) or (b)
above. The indemnifying party shall be entitled to appoint counsel of the
indemnifying party's choice at the indemnifying party's expense to represent the
indemnified party in any action for which indemnification is sought (in which
case the indemnifying party shall not thereafter be responsible for the fees and
expenses of any separate counsel retained by the indemnified party or parties
except as set forth below); provided, however, that such counsel shall be
reasonably satisfactory to the indemnified party. Notwithstanding the
indemnifying party's election to appoint counsel to represent the indemnified
party in an action, the indemnified party shall have the right to employ
separate counsel (including local counsel), and the indemnifying party shall
bear the reasonable fees, costs and expenses of such separate counsel (and local
counsel) if (i) the use of counsel chosen by the indemnifying party to represent
the indemnified party would present such counsel with a conflict of interest,
(ii) the actual or potential defendants in, or targets of, any such action
include both the indemnified party and the indemnifying party, and the
indemnified party reasonably concluded that there may be legal defenses
available to it and/or other indemnified parties that are different from or
additional to those available to the indemnifying party, (iii) the indemnifying
party did not employ counsel satisfactory to the indemnified party to represent
the indemnified party within a reasonable time after notice of the institution
of such action or (iv) the indemnifying party authorized the indemnified party
to employ separate counsel at the expense of the indemnifying party. An
indemnifying party shall not, without the prior written consent of the
indemnified parties, settle or compromise or consent to the entry of any
judgment with respect to any pending or threatened claim, action, suit or
proceeding for which indemnification or contribution may be sought hereunder
(whether or not the indemnified parties are actual or potential parties to such
claim or action), unless such settlement, compromise or consent includes an
unconditional release of each indemnified party from all liability arising out
of such claim, action, suit or proceeding and does not include a statement as to
or an admission of fault, culpability or a failure to act, by or on behalf of
the indemnified party.

      (d) In the event that the indemnity provided in paragraph (a) or (b) of
this Section 7 is unavailable or insufficient to hold harmless an indemnified
party for any reason, then each applicable indemnifying party, in lieu of
indemnifying such indemnified party, shall have a joint and several obligation
to contribute to the aggregate losses, claims, damages and liabilities
(including legal or other expenses reasonably incurred in connection with
investigating or defending same) (collectively "Losses") to which such
indemnified party may be subject in such proportion as is appropriate to reflect
the relative benefits 


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<PAGE>   11

received by such indemnifying party, on the one hand, and such indemnified
party, on the other hand, from the Initial Placement and the Shelf Registration
Statement that resulted in such Losses; provided, however, that in no case shall
any Initial Purchaser or any subsequent Holder of any Note be responsible, in
the aggregate, for any amount in excess of the purchase discount or commission
applicable to such Note, as set forth on the cover page of the Final Offering
Memorandum. If the allocation provided by the immediately preceding sentence is
unavailable for any reason, the indemnifying party and the indemnified party
shall contribute in such proportion as is appropriate to reflect not only such
relative benefits, but also the relative fault of such indemnifying party, on
the one hand, and such indemnified party, on the other hand, in connection with
the statements or omissions which resulted in such Losses, as well as any other
relevant equitable considerations. Benefits received by the Company shall be
deemed to be equal to the sum of (x) the total net proceeds from the Initial
Placement (in each case, before deducting expenses) as set forth on the cover
page of the Final Offering Memorandum and (y) the total amount of additional
interest that the Company was not required to pay as a result of registering the
securities covered by the Shelf Registration Statement that resulted in such
Losses. Benefits received by the Initial Purchasers shall be deemed to be equal
to the total purchase discounts and commissions as set forth on the cover page
of the Final Offering Memorandum, and benefits received by any other Holders
shall be deemed to be equal to the value of receiving Notes registered under the
Act. Relative fault shall be determined by reference to whether any alleged
untrue statement or omission relates to information provided by the indemnifying
party, on the one hand, or by the indemnified party, on the other hand. The
parties agree that it would not be just and equitable if contribution were
determined by pro rata allocation or any other method of allocation that does
not take account of the equitable considerations referred to above.
Notwithstanding the provisions of this paragraph (d), 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 guilty of such
fraudulent misrepresentation. For purposes of this Section 7, each person who
controls a Holder within the meaning of either the Act or the Exchange Act and
each director, officer, employee and agent of such Holder shall have the same
rights to contribution as such Holder, and each person who controls the Company
within the meaning of either the Act or the Exchange Act, each officer of the
Company who shall have signed the Shelf Registration Statement and each director
of the Company shall have the same rights to contribution as the Company,
subject in each case to the applicable terms and conditions of this paragraph
(d).

      (e) The provisions of this Section 7 shall remain in full force and
effect, regardless of any investigation made by or on behalf of any Holder or
the Company or any of the officers, directors or controlling persons referred to
in Section 7 hereof, and will survive the sale by a Holder of Transfer
Restricted Securities or Exchange Notes.

SECTION 8. RULE 144A and RULE 144

      The Company agrees with each Holder, for so long as any Transfer
Restricted Securities remain outstanding and during any period in which the
Company (i) is not subject to Section 13 or 15(d) of the Exchange Act, to make
available, upon request of any Holder, to such Holder or beneficial owner of
Transfer Restricted Securities in connection with any sale thereof and any
prospective purchaser of such Transfer Restricted Securities designated by such
Holder or beneficial owner, the information required by Rule 144A(d)(4) under
the Act in order to permit resales of such Transfer Restricted Securities
pursuant to Rule 144A, and (ii) is subject to Section 13 or 15 (d) of the
Exchange Act, to make all filings required thereby in a timely manner in order
to permit resales of such Transfer Restricted Securities pursuant to Rule 144.

SECTION 9. MISCELLANEOUS


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<PAGE>   12

      (a) No Inconsistent Agreements. The Company has not, as of the date
hereof, entered into, nor shall it, on or after the date hereof, enter into, any
agreement with respect to its securities that is inconsistent with the rights
granted to the Holders herein or otherwise conflicts with the provisions hereof.

      (b) Amendments and Waivers. The provisions of this Agreement, including
the provisions of this sentence, may not be amended, qualified, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the Company has obtained the written consent of the
Holders of at least a majority of the then outstanding aggregate principal
amount of Notes; provided, however, that with respect to any matter that
directly or indirectly affects the rights of any Initial Purchaser hereunder,
the Company shall obtain the written consent of each such Initial Purchaser
against which such amendment, qualification, supplement, waiver or consent is to
be effective. Notwithstanding the foregoing (except the foregoing proviso), a
waiver or consent to depart from the provisions hereof, with respect to a
matter, which relates exclusively to the rights of Holders whose securities are
being sold pursuant to a Shelf Registration Statement and does not directly or
indirectly affect the rights of other Holders, may be given by the Majority
Holders, determined on the basis of Notes being sold rather than registered
under such Shelf Registration Statement.

      (c) Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand-delivery, first-class mail,
telex, telecopier, or air courier guaranteeing overnight delivery:

            (i) if to a Holder, at the most current address given by such holder
      to the Company in accordance with the provisions of this Section 9(c),
      which address initially is, with respect to each Holder, the address of
      such Holder maintained by the registrar under the Indenture or the
      Exchange Note Indenture, as the case may be, with a copy in like manner to
      Morgan Stanley & Co. Incorporated;

            (ii) if to the Initial Purchasers, initially at the respective
      addresses set forth in the Purchase Agreement; and

            (iii) if to the Company, initially at its address set forth in the
      Purchase Agreement.

      All such notices and communications shall be deemed to have been duly
given when received.

      The Initial Purchasers or the Company by notice to the other may designate
additional or different addresses for subsequent notices or communications.

      (d) Successors and Assigns. This Agreement shall inure to the benefit of,
and be binding upon, the successors and assigns of each of the parties hereto,
including, without the need for an express assignment or any consent by the
Company thereto, subsequent Holders of Notes. The Company hereby agrees to
extend the benefits of this Agreement to any Holder of Notes and any such Holder
may specifically enforce the provisions of this Agreement as if an original
party hereto.

      (e) Counterparts. This agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original, and all of which taken
together shall constitute one and the same agreement.

      (f) Headings. The headings in this agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.


                                       12
<PAGE>   13

      (g) Governing Law. This agreement shall be governed by and construed in
accordance with the internal laws of the State of New York applicable to
agreements made and to be performed in said State (without reference to the
conflict of law rules thereof).

      (h) Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstances, is held
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of any such provision in every other respect and the
remaining provisions hereof shall not be in any way impaired or affected
thereby, it being intended that all of the rights and privileges of the parties
shall be enforceable to the fullest extent permitted by law.

      (i) Notes Held by the Company, etc. Whenever the consent or approval of
Holders of a specified percentage of principal amount of Notes is required
hereunder, Notes held by the Company or its Affiliates (other than subsequent
Holders of Notes if such subsequent Holders are deemed to be Affiliates solely
by reason of their holdings of such Notes) shall not be counted in determining
whether such consent or approval was given by the Holders of such required
percentage.

      (j) Entire Agreement. This Agreement is intended by the parties as a final
expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto with respect
to the subject matter contained herein. There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein
with respect to the registration rights granted with respect to the Transfer
Restricted Securities. This Agreement supersedes all prior agreements and
understandings between the parties with respect to such subject matter.


                                       13
<PAGE>   14

      IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                    NTL INCORPORATED

                                    By: /s/ Richard J. Lubasch
                                        -----------------------------------
                                        Name:  Richard J. Lubasch
                                        Title: Senior Vice President, 
                                               General Counsel and Secretary

Donaldson, Lufkin & Jenrette
   Securities Corporation
Morgan Stanley & Co. Incorporated
Chase Securities Inc.
Goldman, Sachs & Co.
BT Alex. Brown Incorporated
Salomon Smith Barney Inc
Walburg Dillon Read LLC

By: Donaldson, Lufkin & Jenrette Securities Corporation


By: /s/ Michael J. Connelly
    ---------------------------
     Name:  Michael J. Connelly
     Title:


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