Dec. 26 (Bloomberg) -- Billionaire Warren Buffett, the chairman of Berkshire Hathaway Inc., said he rebuffed U.S. financial firms that approached him recently about buying stakes in their companies.

``We've seen some deals as you can imagine in this period,'' when banks and securities firms have been hurt by subprime mortgage losses, Buffett, whose company is based in Omaha, Nebraska, said today in an interview on CNBC. ``So far, we have not seen a deal that causes me to start salivating.'' Buffett didn't say which firms contacted him.

Merrill Lynch & Co., Citigroup Inc., Morgan Stanley and Bear Stearns Cos. shored up capital in the past three months as the value of mortgage-related assets plummeted. The New York-based firms struck agreements to obtain a total of $18.5 billion from government-run companies in Singapore, China and Abu Dhabi. Buffett on Oct. 18 denied a New York Times report that he might buy as much as 20 percent of Bear Stearns.

Buffett, 77, has invested in Wall Street before. He injected $700 million into Salomon Inc. in 1987 to help the firm head off a takeover attempt by financier Ronald Perelman.

``People know our phone number, and we haven't seen anything we wanted to move on,'' he said today. ``That doesn't mean we won't in the next six months.''

Buffett said that because of credit market turmoil it's ``certainly possible the big banks are not going to hit their highs on earnings for a few years.''

Trail of Losses

Merrill Lynch, the third-largest U.S. securities firm, said Dec. 24 that it would receive a cash infusion of as much as $6.2 billion from Singapore's Temasek Holdings Pte. and mutual fund manager Davis Selected Advisors LP.

Merrill, which posted a $2.2 billion third-quarter loss on $8.4 billion of writedowns, may be forced to take another $8.6 billion charge next month, according to David Trone, an analyst at Fox-Pitt Kelton Cochrane Caronia Waller. Merrill is a passive, minority investor in Bloomberg LP, the parent of Bloomberg News.

Citigroup said Nov. 27 that Abu Dhabi's sovereign wealth fund would invest $7.5 billion, after the biggest U.S. bank estimated at least $9 billion of fourth-quarter writedowns. State-controlled China Investment Corp. is injecting $5 billion into Morgan Stanley after the second-biggest U.S. securities firm wrote down $9.4 billion of mortgage-related debt.

Bear Stearns, the fifth-largest, struck an agreement in October with China's government-controlled Citic Securities Co. for a $1 billion cross-investment. The New York-based company announced a $1.9 billion writedown Dec. 20, sending the firm to its first quarterly loss since it went public in 1985.

Bond Insurers

Buffett may provide capital relief for bond insurers such as Ambac Financial Group Inc. and MBIA Inc., the Wall Street Journal reported on Nov. 13, citing people familiar with the matter.

Bond insurers have been told by Moody's Investors Service, Standard & Poor's and Fitch Ratings that they need to raise capital to protect their AAA credit ratings after downgrades of securities they guarantee backed by subprime mortgages.

MBIA already has announced an agreement with private equity firm Warburg Pincus under which it will raise $1 billion through the sale of shares. Ambac reinsured $29 billion of its guarantees, freeing up $255 million of capital.

To contact the reporter on this story: Hugh Son in New York at hson1@bloomberg.net.

Last Updated: December 26, 2007 12:31 EST