Warren Buffett yesterday struck the biggest deal of his life with the $26.6bn (£16.2bn) purchase of Burlington Northern Santa Fe, one of the largest US railroad operators, in what the billionaire investor called an "all-in wager" on America's economic future.

The cash-and-shares deal by Mr Buffett's Berkshire Hathaway, which already has a 22.6 per cent stake in BNSF, caps a long search by the legendary investor for an "elephant" deal to deploy his vast cash pile.