<PAGE>   1
                                                                   EXHIBIT 10.35

                                             (EXHIBIT E TO THE CREDIT AGREEMENT)

                    [FORM OF GUARANTEE ASSUMPTION AGREEMENT]


                         GUARANTEE ASSUMPTION AGREEMENT

         GUARANTEE ASSUMPTION AGREEMENT dated as of [_______________, 199_], by
[_______________________], a [______________ corporation/limited liability
company/partnership] (the "Additional Subsidiary Guarantor"), in favor of THE
CHASE MANHATTAN BANK, as administrative agent for the lenders party to the
Credit Agreement referred to below (in such capacity together with its
successors in such capacity, the "Administrative Agent").

         Iridium Operating LLC, a Delaware limited liability company, certain
lenders named therein (the "Lenders"), the Global Arrangers, the Administrative
Agent and the Documentation Agent are parties to a Credit Agreement dated as of
December 19, 1997 (as modified, supplemented or otherwise modified and in effect
from time to time, the "Credit Agreement", the terms defined therein and not
otherwise defined herein being used as therein defined).

         Pursuant to Section 6.11 of the Credit Agreement, the Additional
Subsidiary Guarantor hereby agrees to become a "Subsidiary Guarantor" for all
purposes of the Subsidiary Guarantee Agreement, and an "Obligor" for all
purposes of the Security Agreement. Without limiting the generality of the
foregoing, the Additional Subsidiary Guarantor hereby, jointly and severally
with the other Subsidiary Guarantors, guarantees to each Lender and each Agent
and their respective successors and assigns the prompt payment in full when due
(whether at stated maturity, by acceleration or otherwise) of all Guaranteed
Obligations (as defined in the Subsidiary Guarantee Agreement) in the same
manner and to the same extent as is provided in Article II of the Subsidiary
Guarantee Agreement. In addition, the Additional Subsidiary Guarantor hereby
makes the representations and warranties set forth in Article III of the
Subsidiary Guarantee Agreement, and in Article II of the Security Agreement,
with respect to itself and its obligations under this Agreement (with any
reference in said Sections to the Credit Documents being deemed to include a
reference to this Agreement). In addition, Annexes 1, 2, 3, 4, 5 and 6 to the
Security Agreement shall be deemed to be supplemented in respect of the
Additional Subsidiary Guarantor as specified in Appendix A hereto.



                         Guarantee Assumption Agreement
<PAGE>   2
                                      - 2 -



         IN WITNESS WHEREOF, the Additional Subsidiary Guarantor has caused this
Guarantee Assumption Agreement to be duly executed and delivered as of the day
and year first above written.


                                       [ADDITIONAL SUBSIDIARY GUARANTOR]



                                       By_______________________
                                         Title:


Accepted and Agreed:

THE CHASE MANHATTAN BANK,
  as Administrative Agent


By_________________________
  Title:



                         Guarantee Assumption Agreement
<PAGE>   3
                                      - 3 -


                                                         Appendix A to Guarantee
                                                            Assumption Agreement



Supplement to Annex 1:

         [To be completed]



Supplement to Annex 2:

         [To be completed]



Supplement to Annex 3:

         [To be completed]



Supplement to Annex 4:

         [To be completed]



Supplement to Annex 5:

         [To be completed]



Supplement to Annex 6:

         [To be completed]



                         Guarantee Assumption Agreement