Federal regulatory approval will be necessary. BNSF's vice president of government affairs said the current BNSF management team will remain in place and that the railroad would continue to be headquartered in Ft. Worth.

Berkshire, which already has major stake in the company, said it would acquire the remaining 77.4 percent of the company in a cash-and-stock offer worth $100 per share.

Widely regarded as both one of the world's richest men and the investment community's more brilliant minds, Buffett called his firm's investment an "all-in wager on the economic future of the United States."

"Our country's future prosperity depends on its having an efficient and well-maintained rail system," Buffett said in a statement.

BNSF shares soared 29 percent in pre-market trading on the news.

(The preceding article was published Nov. 3, 2009, by CNN Moneyline.)