TERMINATION AGREEMENT IN RESPECT OF FOREIGN GUARANTEE AGREEMENT

Exhibit 99.6

TERMINATION AGREEMENT IN RESPECT OF FOREIGN
GUARANTEE AGREEMENT

     TERMINATION AGREEMENT dated as of October 24, 2005 among JPMORGAN CHASE BANK, N.A. and NORTEL NETWORKS UK LIMITED and certain other financial institutions.

     WHEREAS, Nortel Networks UK Limited (“ Nortel Networks UK ”) and JPMorgan Chase Bank, N.A. (the “ Collateral Agent ”) entered into the NNL Foreign Subsidiary Guarantee dated as of April 4, 2002, as amended December 12, 2002 (the “ UK Guarantee ”);

     WHEREAS, Nortel Networks UK desires to terminate the UK Guarantee pursuant to Section 14 thereof; and

     WHEREAS, NNL, Nortel Networks UK and certain of NNL’s other Subsidiaries have delivered a termination request letter dated October 24, 2005 to the Collateral Agent and Export Development Corporation (“ EDC ”) requesting the Collateral Agent to terminate the UK Guarantee pursuant to Section 14 thereof;

     WHEREAS, EDC has consented to the termination of the UK Guarantee pursuant to Section 14 thereof;

     NOW, THEREFORE, in consideration of the foregoing and other good and valuable consideration, the r