US STOCKS-Futures extend gains on Buffett rescue plan

(Updates with Buffett comments)

NEW YORK, Feb 12 (Reuters) -U.S. stock index futures extended gains on Tuesday after billionaire investor Warren Buffett said on CNBC that Berkshire Hathaway has offered to take over liabilities for bond insurers. For details, see [ID:nWEN3902]

S&P 500 futures SPc1 rose 8.80 points, above fair value, a mathematical formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract.

Dow Jones industrial average futures DJc1 rose 72 points. Nasdaq 100 NDc1 futures rose 11.25 points. (Reporting by Kristina Cooke; Editing by Kenneth Barry)