EXHIBIT 10.25 December 14, 2001 Ms. Susan Baratta BNY Capital Markets, Inc. Agency Function Administration One Wall Street 18th floor New York, New York 10286 Dear Ms. Baratta: I refer to the Amended and Restated Credit Agreement, dated as of December 2, 2000 as amended and restated as of June 30, 2001 (the "Agreement") among Ambac Assurance Corporation (the "Borrower"), various banks (the "Banks"), Bank of America, N.A. and Deutsche Bank AG, New York Branch, (the "Co-Syndication Agents") and The Bank of New York (the "Administrative Agent"). In accordance with Section 3.02 of the Agreement, the Borrower hereby gives notice of termination of i) $400 million of Unutilized Commitments pro-rata among the Banks and between the Municipal Tranche Commitment and the Structured Tranche Commitment, ii) $86 million of Unutilized Contingent Commitments from Swiss Re Financial Products Corporation, iii) $10 million of Unutilized Contingent Commitments from Bayerische Landesbank Girozentrale, and iv) $33 million of Unutilized Contingent Commitments from Cooperative Centrale Raiffeisen Boerenleenbank B.A., "Rabobank Nederland", New York Branch. The termination of the Unutilized Commitments and Unutilized Contingent Commitments should be effective as of December 21, 2001. Please sign below and fax to me at 212.208.3108 to confirm your receipt of this Notice. Sincerely, Robert W. Starr RECEIVED: The Bank of New York as Administrative Agent By _________________________ Title: cc. Frank Bivona Louis DiFranco David Trick Lizanne Eberle Bill Giusti