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                                                                   EXHIBIT 10.31

                                             (EXHIBIT A TO THE CREDIT AGREEMENT)

                       [FORM OF ASSIGNMENT AND ACCEPTANCE]


                            ASSIGNMENT AND ACCEPTANCE

                  Reference is made to the Credit Agreement dated as of December
19, 1997 (as amended, supplemented or otherwise modified and in effect on date
hereof, the "Credit Agreement") among Iridium Operating LLC, a Delaware limited
liability company, the lenders named therein, the Global Arrangers, The Chase
Manhattan Bank, as administrative agent for such lenders and or collateral
agent, and Barclays Capital, the investment banking division of Barclays Bank
PLC, as documentation agent thereunder. Terms defined in the Credit Agreement
are used herein with the same meanings.

                  The Assignor named below hereby sells and assigns, without
recourse, to the Assignee named below, and the Assignee hereby purchases and
assumes, without recourse, from the Assignor, effective as of the Assignment
Date set forth below, the interests set forth below (the "Assigned Interest") in
the Assignor's rights and obligations under the Credit Agreement, including,
without limitation, the interests set forth below in the Commitment of the
Assignor on the Assignment Date and Loans owing to the Assignor which are
outstanding on the Assignment Date, together with unpaid interest accrued on the
assigned Loans to the Assignment Date, and the amount, if any, set forth below
of the fees accrued to the Assignment Date for the account of the Assignor. The
Assignee hereby acknowledges receipt of a copy of the Credit Agreement. From and
after the Assignment Date (i) the Assignee shall be a party to and be bound by
the provisions of the Credit Agreement and, to the extent of the interests
assigned by this Assignment and Acceptance, have the rights and obligations of a
Lender thereunder and (ii) the Assignor shall, to the extent of the interests
assigned by this Assignment and Acceptance, relinquish its rights and be
released from its obligations under the Credit Agreement.

                  The Assignor (a) makes no representation or warranty and
assumes no responsibility with respect to any statements, warranties or
representations made in or in connection with the Credit Agreement or the
execution, legality, validity, enforceability, genuineness, sufficiency or value
of the Credit Agreement, any other Credit Document or any instrument or document
furnished pursuant thereto, other than that it has not created any adverse claim
upon the interest being assigned by it hereunder and that such interest is free
and clear of any adverse claim; and (b) makes no representation or warranty and
assumes no responsibility with respect to the financial condition of the
Company, any of its Subsidiaries or any other Project Party or the performance
or observance by the Company, any of its Subsidiaries or any other Project Party
of any of their respective obligations under the Credit Agreement or any other
Transaction Document or any other instrument or document furnished pursuant
hereto or thereto.

                  The Assignee (a) represents and warrants that it is legally
authorized to enter into this Assignment and Acceptance; (b) confirms that it
has received such documents and



                            Assignment and Acceptance
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information as it has deemed appropriate to make its own credit analysis and
decision to enter into this Assignment and Acceptance; (c) agrees that it will,
independently and without reliance upon the Assignor, the Agents or any other
person that has become a Lender and based on such documents and information as
it shall deem appropriate at the time, continue to make its own credit decisions
in taking or not taking action under the Credit Agreement; and (d) appoints and
authorizes (i) the Administrative Agent to take such action as agent on its
behalf and to exercise such powers under the Credit Agreement and the other
Credit Documents to which it is a party as are delegated to the Administrative
Agent by the terms thereof and (ii) the Collateral Agent to take such action as
agent on its behalf and to exercise such powers under the Credit Documents to
which it is a party as are delegated to the Collateral Agent by the terms
thereof, together, in each case, with such powers as are incidental thereto.

                  This Assignment and Acceptance is being delivered to the
Administrative Agent together with (i) if the Assignee is a Foreign Lender, any
documentation required to be delivered by the Assignee pursuant to Section
2.15(e) of the Credit Agreement, duly completed and executed by the Assignee,
and (ii) if the Assignee is not already a Lender under the Credit Agreement, an
administrative questionnaire in the form supplied by the Administrative Agent,
duly completed by the Assignee. The [Assignee/Assignor] shall pay the fee
payable to the Administrative Agent pursuant to Section 11.04(b) of the Credit
Agreement.

                  This Assignment and Acceptance shall be governed by and
construed in accordance with the laws of the State of New York.

 

                            Assignment and Acceptance
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Date of Assignment:

Legal Name of Assignor:

Legal Name of Assignee:

Assignee's Address for Notices:

Effective Date of Assignment
("Assignment Date"):


                          Percentage Assigned of                           
                                                                           
                          Facility/Commitment                              
                                                                           
                          (set forth, to at                                
                                                                           
                                                    least 8 decimals, as a 
                                                    percentage of the      
                                                    Facility and the 
                                                    aggregate Commitments
                          Principal Amount          of all Lenders         
Facility                  Assigned                  thereunder             

Commitment Assigned:      $
                                               
Loans:                                         
                                                                             %



Fees Assigned (if any):


The terms set forth above are hereby agreed to as of [_____________]:

                                        [NAME OF ASSIGNOR], as Assignor


                                        By_____________________________
                                          Name:
                                          Title:

                                        [NAME OF ASSIGNEE], as Assignee




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                                     By______________________________
                                       Name:
                                       Title:


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The undersigned hereby consent to the within assignment:(1)

IRIDIUM OPERATING LLC



By_________________________
   Name:
   Title:


THE CHASE MANHATTAN BANK,
  as Administrative Agent



By_________________________
   Name:
   Title:
--------

(1)      Consents to be included to the extent required by Section 11.04(b) of
         the Credit Agreement.


                            Assignment and Acceptance