Warren Buffett has rediscovered his appetite for junk bonds, buying $2.1bn in debt issued by the Texas utility TXU in a move that suggests value-seeking investors are prepared to step back into the troubled credit markets.

The decision by the "Sage of Omaha" to spend part of his $47bn war chest on the discounted TXU bonds comes as other value investors such as Wilbur Ross have taken advantage of the credit squeeze to buy assets and securities at attractive prices.