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                                                                   EXHIBIT 10.28

                           SERIES A SUBORDINATED NOTE

                                    IPO NOTE

                        KHANTY MANSIYSK OIL CORPORATION

     THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
     UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR UNDER STATE SECURITIES
     LAWS. THE TRANSFER OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE IS
     SUBJECT TO THE CONDITIONS SPECIFIED IN A SHARE PURCHASE AGREEMENT DATED
     JUNE 29, 2000 AND A SHAREHOLDER AGREEMENT DATED JUNE 29, 2000. A COPY OF
     SUCH CONDITIONS WILL BE FURNISHED BY THE COMPANY TO THE HOLDER HEREOF UPON
     WRITTEN REQUEST AND WITHOUT CHARGE. THESE SECURITIES MAY NOT BE RESOLD OR
     TRANSFERRED UNLESS SUCH CONDITIONS ARE COMPLIED WITH AND UNLESS REGISTERED
     OR EXEMPT FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933 AND APPLICABLE
     STATE SECURITIES LAWS.

                                PROMISSORY NOTE

US$ 10,005,925                                                    June 30, 2000

     FOR VALUE RECEIVED, Khanty Mansiysk Oil Corporation, a Delaware
corporation (the "COMPANY"), hereby promises to pay to the order of Waldo
Securities S.A. (the "LENDER"), a company organized and existing under the
laws of the British Virgin Islands, the principal sum of Ten Million, Five
Thousand Nine Hundred Twenty Five United States Dollars (US$ 10,005,925),
with no interest payable on the outstanding balance thereof from the date
hereof until paid in full (except as otherwise provided in Section 5 of this
Note.

     This Note (the "NOTE") is issued pursuant to and is entitled to the
benefits of, and is subject to the provisions of, the Share Purchase Agreement,
dated June 29, 2000, between the Company and Lender (as amended or otherwise
supplemented from time to time, the "SHARE PURCHASE AGREEMENT"). The Share
Purchase Agreement, among other things, contains provisions for (i) mandatory
redemption by the Company, (ii) optional redemption, with payment, at option of
Company, in cash or the delivery of shares of common stock of the Company, or a
combination thereof (subject to adjustment pursuant to Section 2.4(a) thereof),
(iii) restrictions on transfer of the Note, and (iv) exchange of Notes in
denominations of US$ 100,000 or integral multiples thereof.

     Capitalized terms used but not defined herein shall have the meanings
assigned to such terms in the Share Purchase Agreement.

     This Note is also subject to the following terms and conditions:

     1. NO INTEREST. No interest shall accrue or be payable at any time on the
unpaid principal amount of the Note, except as otherwise provided in Section 5
of this Note.

     2. PAYMENT OF PRINCIPAL. Unless sooner declared due hereunder or earlier
redeemed in accordance with the Share Purchase Agreement, the principal amount
of this Note shall be paid on the date fixed for such payment pursuant to
Section 2.4(a) of the Share Purchase Agreement.

     3. METHOD OF PAYMENT. Payments of principal shall be made in United States
Dollars by wire transfer in immediately available funds to the account specified
by the Lender or other holder of this Note (the "HOLDER"); provided, however,
that in the event of redemption of the Note pursuant to Section 2.4 of the Share
Purchase Agreement, payment of the outstanding principal may be made, at the
option of Company, in cash or in common stock of the Company or a combination
thereof. Principal shall be paid at such place as the Holder may designate in
writing to the Company. The

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Holder must surrender this Note to the Company upon the earlier of the
redemption hereof in accordance with the Share Purchase Agreement or at the time
of final payment of principal.

     4. PREPAYMENT. The Company shall have the right to prepay this Note prior
to maturity in accordance with the Share Purchase Agreement without the consent
of the Lender.

     5. INTEREST AFTER DUE DATE. If the principal of this Note is not paid when
due, as a result of redemption or otherwise, the overdue amount shall bear
interest from the due date until paid at an annual rate of 12%.

     6. INTEREST SAVINGS CLAUSE. Notwithstanding any other provision hereof, the
interest payable hereunder shall be limited to the maximum amount permitted
under applicable law. If any amount is paid hereunder which would be usurious
under applicable law, it shall be deemed a payment of principal or shall be
promptly refunded to the Company as necessary to avoid violation of any
applicable usury laws.

     7. APPLICATION OF PAYMENTS. All payments received on this Note shall first
be applied to the payment of any accrued interest (if any) pursuant to Section 5
of this Note and then to the reduction of principal.

     8. WAIVERS. The Company, for itself and its successors and assigns and any
endorsers of this Note from time to time hereby waives presentment for payment,
demand, notice of dishonor, protest, notice of protest and any other notice not
provided for in the Share Purchase Agreement that the Company may lawfully
waive. No delay in exercising any right under this Note shall operate as a
waiver of such right or any other right under this Note, nor shall any omission
in exercising any right on the part of Holder under this Note operate as a
waiver of any other rights. The remedies provided herein are cumulative and not
exclusive of any remedies provided by law.

     9. ATTORNEY'S FEES. If this Note or interest thereon is not paid when
due, or if it is brought to enforce any right hereunder, the Company and each
successor, assignee and endorser of Note agrees to pay all reasonable costs
of collection and enforcement, including reasonable attorneys' fees. In the
event of any bankruptcy or insolvency proceedings involving the Company,
costs of collection shall include all costs and attorneys' fees incurred in
connection with such proceedings, including the fees of counsel for
attendance at meetings of creditors.

     10. RIGHTS AND PRIORITIES. The rights and priorities of the Holders of this
Note with respect to payment of interest and principal shall be subordinated in
right of payment to the notes issued by the Company pursuant to the
US$ 55,000,000 financing conducted by the Company in October 1997 (the "SENIOR
FINANCING") and shall rank PARI PASSU with the rights and priorities of all
other current and future unsecured indebtedness of the Company of similar size
(being less than US$ 10 Million) and tenor.

     11. SUBORDINATION.

     (a)  The indebtedness of the Company evidenced hereunder shall be junior
          and subordinate to the Senior Debt. As used in this Note, the term
          "SENIOR DEBT" means: (i) all securities issued by the Company pursuant
          to the Senior Financing and (ii) any refundings, renewals or
          extensions of any indebtedness described in clause (i) above.

     (b)  In the event of any dissolution, winding up, liquidation,
          reorganization or other similar proceedings relative to the Company,
          its property or its operations (whether in bankruptcy, insolvency or
          receivership proceedings, or upon an assignment for the benefit of
          creditors, or any other marshalling of assets of the Company or
          otherwise), then all Senior Debt shall first be paid in full in cash
          or cash equivalents before the Company shall be entitled to retain
          any payment or distribution of assets made after such event with
          respect to the Notes. In any such proceeding, any payment or
          distribution of assets to which the Holder would be entitled if the
          Notes were not subordinated to the Senior Debt shall be paid by the
          trustee or agent or other person making such payment or distribution,
          or by the Holder if received by it, directly to the

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          holders of the Senior Debt (pro rata) to the extent necessary to make
          payment in full of all Senior Debt remaining unpaid, after giving
          effect to any concurrent payment or distribution to or for the holders
          of the Senior Debt.

     (c)  The Company may, from time to time (and with respect to payments of
          principal of the Notes, upon 30-days prior written notice to the
          holders of the Senior Debt), pay or cause to be paid to the Holder and
          the Holder may accept and retain scheduled payments in respect of
          interest and principal on the Notes, as originally executed and
          delivered, unless at the time of any such proposed payment or
          immediately after giving effect thereto, there shall exist any default
          with respect to the Senior Debt that permits holders of the Senior
          Debt as to which such default relates to accelerate in maturity (each,
          a "SENIOR EVENT OF DEFAULT") and the holders of the Senior Debt have
          notified the Company in writing of the existence of such Senior Event
          of Default prior to such payment. If the Holder receives payment from
          the Company pursuant to this Section 11(c), such payment shall be
          deemed to constitute a representation by the Company to the holders of
          the Senior Debt and to the Holders that no Senior Event of Default
          exists, and that such payment is permitted to be paid to the Holder
          under the Notes; and the Holder shall be entitled to keep and retain
          such payments, unless the holders of the Senior Debt shall have
          notified the Company of the Holder of a Senior Event of Default in
          writing prior to such payment, in which case (if such Senior Event of
          Default in fact existed on the date of such payment) the Holder shall
          forthwith deliver such payment or an amount of cash equal thereof to
          the holders of the Senior Debt for application in payment of the
          Senior Debt.

     (d)  In the event that the Holder shall receive any payment or distribution
          of assets which the Holder is not entitled to retain under the
          provisions of the Note, the Holder shall hold any amount so received
          in trust for the holders of Senior Debt and, upon the request of any
          holder of Senior Debt, shall forthwith turn over such payment or
          distribution (without liability for interest thereon) to the holders
          of Senior Debt (pro rata) in the form received to be applied to Senior
          Debt. Any holder of Senior Debt may at any time and from time to time
          without the consent of or notice to the Holder: (i) extend, renew,
          modify or amend the terms of Senior Debt; (ii) sell, exchange, release
          or otherwise deal with any property pledged, mortgaged or otherwise
          securing Senior Debt; (iii) release any guarantor or any other person
          (except the Company) liable in any manner for the Senior Debt; (iv)
          exercise or refrain from exercising any rights against the Company or
          any other person; and (v) apply any sums by whomever paid or however
          realized to Senior Debt. Any and all of such actions set forth in this
          Section 11 may be taken by holders of Senior Debt without incurring
          responsibility to the Holder and without impairing or releasing the
          obligations of the Holder under this Section 11.

     (e)  No holders of Senior Debt shall be prejudiced in its right to enforce
          subordination of the Notes by any act or failure to act by the Company
          or anyone in custody of the Company's assets or property. No amendment
          or modification of the terms of this Section 11 shall be effective as
          against any holder of Senior Debt without the consent of such holder.

     12. NOTICES. Any notice, request, demand, consent, approval or other
communication which the Company or the Holder are obligated or may elect to give
hereunder shall be given in the form and in the manner set forth in the Share
Purchase Agreement for the giving of notices thereunder and shall be deemed
given for the purposes hereof at such time as the same, if given under the Share
Purchase Agreement, would be deemed given.

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     13. SEVERABILITY. If any provision of this Note or the application thereof
to any party or circumstances is held invalid or unenforceable, the remainder of
this Note and the application of such provision to other parties or
circumstances will not be affected thereby and the provisions of this Note shall
be several in any such instance.

     14. GOVERNING LAW. This Note shall be governed by and interpreted in
accordance with the laws of the State of New York applicable to agreements made
and to be performed within such State.

                                        KHANTY MANSIYSK OIL CORPORATION

                                        By:
                                            -----------------------------
                                            Name: John B. Fitzgibbons
                                            Title: Chief Executive Officer

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                                                               EXHIBIT 10.29

                           SERIES B SUBORDINATED NOTE

                                  REMAINDER NOTE

                         KHANTY MANSIYSK OIL CORPORATION

          THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
          REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR UNDER
          STATE SECURITIES LAWS. THE TRANSFER OF THE SECURITIES REPRESENTED
          BY THIS CERTIFICATE IS SUBJECT TO THE CONDITIONS SPECIFIED IN A
          SHARE PURCHASE AGREEMENT DATED JUNE 29, 2000 AND A SHAREHOLDERS
          AGREEMENT DATED JUNE 29, 2000. A COPY OF SUCH CONDITIONS WILL BE
          FURNISHED BY THE COMPANY TO THE HOLDER HEREOF UPON WRITTEN REQUEST
          AND WITHOUT CHARGE. THESE SECURITIES MAY NOT BE RESOLD OR
          TRANSFERRED UNLESS SUCH CONDITIONS ARE COMPLIED WITH AND UNLESS
          REGISTERED OR EXEMPT FROM REGISTRATION UNDER THE SECURITIES ACT OF
          1933 AND APPLICABLE STATE SECURITIES LAWS.

                                  PROMISSORY NOTE

US$ 10,000,000                                       June 30, 2000

          FOR VALUE RECEIVED, Khanty Mansiysk Oil Corporation, a Delaware
Corporation (the "COMPANY"), hereby promises to pay to the order of Waldo
Securities S.A. (the "LENDER"), a company organized and existing under the
laws of the British Virgin Islands, the principal sum of Ten Million United
States Dollars (US$ 10,000,000), with no interest payable on the outstanding
balance thereof from the date hereof until December 31, 2000, and from
January 1, 2001 until paid in full with interest on the outstanding balance
thereof at the rate of 10% per annum (or at such increased rate required to
be paid in accordance with Section 7 of this Note).

          This Note (the "NOTE") is issued pursuant to and is entitled to
the benefits of, and is subject to the provisions of, the Share Purchase
Agreement, dated June 29, 2000, between the Company and Lender (as amended or
otherwise supplemented from time to time, the "SHARE PURCHASE AGREEMENT").
The Share Purchase Agreement, among other things, contains provisions for (i)
optional redemption, (ii) restrictions on transfer of the Note, and (iii)
exchange of Notes in denominations of $100,000 or integral multiples thereof.

          Capitalized terms used but not defined herein shall have the
meanings assigned to such terms in the Share Purchase Agreement.

          This Note is also subject to the following terms and conditions:

          1. COMPUTATION AND PAYMENT OF INTEREST. No interest shall accrue or
be payable by the Company on the unpaid principal amount of this Note from
the date of this Note until December 31, 2000. Commencing on January 1, 2001,
the Company shall pay interest on the unpaid principal amount of the Note
until such principal amount shall be paid in full, at a rate equal to 10% per
annum. Accrued interest on the unpaid principal amount of the Note shall be
payable quarterly on September 30, December 31, March 31 and June 30 of each
year until the Note is paid in full with the first cash payment due on March
31, 2001. The Company shall make each payment under the Note year to the
holder thereof, as determined by the reference to the Company's note
registration books on the first day of relevant month when payment is due not
later than 12:00 noon, New York City Time, on the day when due. All
computations of interest shall be made on the basis of a year of 365 or 366
days, as the case may be, in each case for the actual number of days
(including the first day but excluding the last day) elapsed. Whenever any
payment under the Note shall be stated to be

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due on a day other than a Business Day, such payment shall be made on the
next succeeding Business Day, and such extension of time shall in such case
be included in the computation of payment of interest.

          2. PAYMENT OF PRINCIPAL. Unless sooner declared due hereunder or
earlier redeemed in accordance with the Share Purchase Agreement, the
principal amount of this Note shall be paid on the date fixed for such
payment pursuant to Section 2.2(b) of the Share Purchase Agreement.

          3. METHOD OF PAYMENT. Payments of principal shall be made in United
States dollars by wire transfer in immediately available funds to the account
specified by the Lender or other holder of this Note (the "HOLDER").
Principal shall be paid at such place as the Holder may designate in writing
to the Company. The Holder must surrender this Note to the Company upon the
earlier of the redemption hereof in accordance with the Share Purchase
Agreement or at the time of final payment of principal.

          4. PREPAYMENT. The Company shall have the right to prepay this Note
prior to maturity in accordance with the Share Purchase Agreement without the
consent of the Lender.

          5. INTEREST AFTER DUE DATE. If the principal of this Note is not
paid when due as a result of redemption or otherwise, the overdue amount
shall bear interest from the due date until at an annual rate of 12%.

          6. INTEREST SAVINGS CLAUSE. Notwithstanding any other provision
hereof, the interest payable hereunder shall be limited to the maximum amount
permitted under applicable law. If any amount paid hereunder which would be
usurious under applicable law, it shall be deemed a payment of principal or
shall be promptly refunded to the Company as necessary to avoid violation of
any applicable usury statute.

          7. APPLICATION OF PAYMENTS. All payments received in this Note
shall first be applied to the payment of any accrued interest (if any)
pursuant to Sections 1 or 5 of this Note and then to the reduction of
principal.

          8. WAIVERS. The Company or itself and its [?succ]essors and assigns
and any endorsers of this Note from time to time hereby waives  presentment
for payment, demand, notice of dishonor, protest, notice of protest and any
other notice not provided for in the Share Purchase Agreement that the
Company may lawfully waive. No delay in exercising any right under this Note
shall operate as a waiver of such right or any other right under this Note,
nor shall any omission in exercising any right on the part of Holder under
this Note operate as a waiver of any other rights. The remedies provided
hereon are cumulative and not exclusive of any remedies provided by law.

          9. ATTORNEYS' FEES. If this Note or interest thereon is not paid
when due, or suit is brought to enforce any right hereunder, the Company and
each successor, assignee and endorser of this Note agrees to pay all
reasonable costs of collection and enforcement, including reasonable
attorneys' fees. In the event of any bankruptcy or insolvency proceedings
involving the Company, costs of collection shall include all costs and
attorneys' fees incurred in connection with such proceedings, including the
fees of counsel for attendance at meetings of creditors.

          10. RIGHTS AND PRIORITIES. The rights and priorities of the Holders
of this Note with respect to payment of interest and principal shall be [?sub]
ordinated in right of payment to the notes issued by the Company pursuant to
the US$ 55,000,000 financing conducted by the Company in October 1997 (the
"SENIOR FINANCING") and shall rank PARI PASSU with the rights and priorities
of all other current and future unsecured indebtedness of the Company of
similar size (being less than US$ 10 Million) and tenor.

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          11. SUBORDINATION.
              (a) The indebtedness of the Company evidenced hereunder shall
                  be junior and subordinate to all Senior Debt. As used in
                  this Note, the term "SENIOR DEBT" means: (i) all securities
                  issued by the Company pursuant to the Senior Financing and
                  (ii) any refundings, renewals or extensions of any
                  indebtedness described in clause (i) above.

              (b) In the event of any dissolution, winding up, liquidation,
                  reorganization or other similar proceedings relative to the
                  Company, its property or its operations whether in
                  bankruptcy, insolvency or receivership proceedings, or upon
                  an assignment for the benefit of creditors, or any other
                  marshalling of assets of the Company or otherwise), then
                  all Senior Debt shall first be paid in full in cash or cash
                  equivalents before the Company shall be entitled to retain
                  any payment or distribution of assets made after such event
                  with respect to the Notes. In any such proceeding, any
                  payment or distribution of assets to which the Holder would
                  be entitled if the Notes were not subordinated to the
                  Senior Debt shall be paid by the trustee or agent or other
                  person making such payment or distribution, or by the
                  Holder if received by it, directly to the holders of the
                  Senior Debt (pro rata) to the extent necessary to make
                  payment in full of all Senior Debt remaining unpaid, after
                  giving effect to any concurrent payment or distribution to
                  or for the holders of the Senior Debt.

              (c) The Company may, from time to time (and with respect to
                  payments of principal of the Notes, upon 30-days prior
                  written notice to the holders of the Senior Debt), pay or
                  cause to be paid to the Holder and the Holder may accept
                  and retain scheduled payments in respect of interest and
                  principal on the Notes, as originally executed and
                  delivered, unless at the time of any such proposed payment
                  or immediately after giving effect thereto, there shall
                  exist any default with respect to the Senior Debt that
                  permits holders of the Senior Debt as to which such default
                  relates to accelerate its maturity (each, as "SENIOR EVENT
                  OF DEFAULT") and the holders of the Senior Debt have
                  notified the Company in writing of the existence of such
                  Senior Event of Default prior to such payment. If the
                  Holder receives payment from the Company pursuant to this
                  Section 11(c), such payment shall be deemed to constitute a
                  representation by the Company to the holders of the Senior
                  Debt and to the Holder that no Senior Event of Default
                  exists, and that such payment is permitted to be paid to the
                  Holder under the Notes; and the Holder shall be entitled to
                  keep and retain such payments, unless the holders of the
                  Senior Debt shall have notified the Company or the Holder
                  of a Senior Event of Default in writing prior to such
                  payment, in which case (if such Senior Event of Default in
                  fact existed on the date of such payment) the Holder shall
                  forthwith deliver such payment or an amount of cash equal
                  thereto to the holders of the Senior Debt for application
                  in payment of the Senior Debt.

              (d) In the event that the Holder shall receive any payment or
                  distribution of assets which the Holder is not entitled to
                  retain under the provisions of the Notes, the Holder shall
                  hold any amount so received in trust for the holders of
                  Senior Debt and, upon the request of any holder of Senior
                  Debt, shall forthwith turn over such payment or
                  distribution (without liability for interest thereon) to
                  the holders of Senior Debt (pro rata) in the form received
                  to be applied to Senior Debt. Any holder of Senior Debt may
                  at any time and from time to time without the consent of or
                  notice to the Holder: (i) extend, renew, modify or amend
                  the terms of Senior Debt; (ii) sell, exchange, release or
                  otherwise deal with any property pledged, mortgaged or
                  otherwise securing Senior Debt; (iii) release any guarantor
                  or any other person (except the Company)

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<PAGE>

                  liable in any manner for the Senior Debt; (iv) exercise or
                  refrain from exercising any rights against the Company or
                  any other person; and (v) apply any sums by whomever paid
                  or however realized to Senior Debt. Any and all of such
                  actions set forth in this Section 11 may be taken by
                  holders of Senior Debt without incurring responsibility to
                  the Holder and without impairing or releasing the
                  obligations of the Holder under this Section 11.

              (e) No holder of Senior Debt shall be prejudiced in its right
                  to enforce subordination of the Notes by any act or failure
                  to act by the Company or anyone in custody of the Company's
                  assets or property. No amendment or modification of the
                  terms of this Section 11 shall be effective as against any
                  holder of Senior Debt without the consent of such holder.

          12. NOTICES. Any notice, request, demand, consent, approval or
other communication which the Company or the Holder are obligated or may
elect to give hereunder shall be given in the form and in the manner set
forth in the Share Purchase Agreement for the giving of notices thereunder
and shall be deemed given for the purposes hereof at such time as the same,
if given under the Share Purchase Agreement, would be deemed given.

          13. SEVERABILITY. If any provision of this Note or the application
thereof to any party or circumstances is held invalid or unenforceable, the
remainder of this Note and the application of such provision to other parties
or circumstances will not be affected thereby and the provisions of this Note
shall be several in any such instance.

          14. GOVERNING LAW. This Note shall be governed by and interpreted
in accordance with the laws of the State of New York applicable to agreements
made and to be performed within such State.

          KHANTY MANSIYSK OIL CORPORATION

          By: ____________________________________
          Name: John B. Fitzgibbons
          Title: Chief Executive Officer

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