The Federal Reserve Bank of New York gave up much of its power in high-pressure negotiations with the American International Group’s trading partners last year, according to a government report made public on Monday.

Just two days before the New York Fed paid A.I.G.’s partners 100 cents on the dollar to tear up their contracts with the insurance giant, one bank volunteered to take a modest haircut  but it never got the chance.

UBS, of Switzerland, alone offered to give a break to the New York Fed in the negotiations last November over how to keep A.I.G. from toppling and taking other banks down with it. It would have accepted 98 cents on the dollar.

But UBS’s good-faith gesture was quickly drowned out by Goldman Sachs and the top French bank regulator. They argued, with others, that it would be improper and perhaps even criminal to force A.I.G.’s trading partners to bear losses outside of bankruptcy court.