Warren Buffett's Berkshire Hathaway has agreed to shed much of its 40-year-old investment in Graham Holdings Co, the former publisher of the Washington Post, and swap most of its shares for a Miami television station and other assets.

Berkshire will exchange about 1.6 million Graham shares, worth roughly $1.1 billion, for Miami station WPLG, an unspecified number of Berkshire shares now owned by Graham, and cash, the companies said in a joint statement today.

“I am sure this is a mutually beneficial transaction for both companies,” Buffett said. “While this transaction will greatly reduce our position in Graham Holdings, our admiration for the company and its management is undiminished.”

Berkshire owns 1.73 million Graham shares that were worth more than $1.2 billion as of yesterday. It paid $11 million for its stake in the middle of 1973.

"Warren Buffett's 40-year association with our company has been extremely good for our shareholders," and WPLG employees can now join "one of the greatest companies in America," said Donald Graham, chief executive officer of Graham Holdings.

The transaction is subject to the completion of final paperwork, regulatory approval and other conditions.

Graham Holdings changed its name from Washington Post Co after selling its flagship paper last year to Amazon. com CEO Jeff Bezos. Its businesses include Kaplan, the education unit founded by Stanley Kaplan.

Mr Buffett (83) stepped down from the Post's board in 2011. He had been a longtime confidant of the late Katharine Graham, the former Post CEO and mother of Donald Graham. (Reuters)