WASHINGTON (Reuters) - Billionaire Warren Buffett's Berkshire Hathaway Inc <BRKa.N> <BRKb.N> won U.S. antitrust approval to take over railroad operator Burlington Northern Santa Fe Corp <BNI.N>, the Federal Trade Commission said on Monday.

Berkshire is on track to buy the 77.4 percent of Burlington Northern it does not already own for $26.4 billion.

The approval was announced in a list of deals cleared by U.S. antitrust regulators that the FTC issues several times a week.

(Reporting by Diane Bartz, editing by Gerald E. McCormick)