Mr Thain’s responsibilities will include operations now held in global corporate and investment banking and most of what is now in global wealth and investment management at Bank of America, which will be merged with similar functions at Merrill Lynch.

A household name with a large wealth management advisory arm and thousands of private client brokers, Merrill has been one of the most high-profile casualties of the credit crunch. It has agreed to be bought by BoA in a $50 billion deal. As BoA does not have much of a wealth management presence outside its domestic market, the deal is not thought by analysts to be bad news for wealth managers at Merrill.

"I am delighted that John has agreed to join Bank of America. His experience and expertise will be invaluable as we put our two companies together and move forward as the premier financial services company in the world,” Ken Lewis, BoA chairman and CEO said in a statement.

Before taking up his present role in 2007, Mr Thain was CEO and a director of NYSE Euronext, the stock exchange group. He joined the New York Stock Exchange in 2004 and has previously held senior positions at Goldman Sachs.

Meanwhile, Mr Lewis also announced that Brian Moynihan will continue as president of global corporate and investment banking at Bank of America until the merger, and will take on a key newly created enterprise-wide role effective immediately. Mr Moynihan will continue as president of GCIB until the merger occurs.

After that, Mr Moynihan will become president of private equity and global operations, reporting to Mr Lewis. The BoA private equity business, LaSalle Global Trust Services, Enterprise Delivery and Technology, Legal, and Supply Chain Management, will begin reporting to him immediately.