Elite US firms Wachtell Lipton Rosen & Katz and Shearman & Sterling have taken the lead advisory roles on the $50bn (£28bn) all-stock sale of banking giant Merrill Lynch to Bank of America.

Bank of America was advised by a 23-strong Wachtell team comprising 12 partners, including Edward Herlihy, co-chairman of the firm’s executive committee, who also last week advised the US Treasury Department on its bailout of mortgage giants Freddie Mac and Fannie Mae.