Warren Buffett the billionaire investor invested $5 billion in Bank of America this week to help prop up the ailing bank. Buffett's cash injection quickly led to the share prices in banks around the world rising yesterday.

Buffett may have earned almost $1 billion in just one day from his investment as Bank of America shares rocketed on the New York stock exchange.

The bank has been struggling due to the hosting market and stock market crisis, and this month it cut 3,500 jobs.

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But Buffett's show of confidence helped to cheer the global banking sector and eased concern the U.S. was slipping towards a double-dip recession.

In an interview quoted in the Daily Mail Buffett said of Bank of America: ‘I am impressed with the profit-generating abilities of this franchise, and that they are acting aggressively to put their challenges behind them. Bank of America is focused on their customers and on serving them well. That’s what customers want.’