Ken Lewis, Bank of America’s chief executive, will testify on Thursday before New York state prosecutors, who plan to grill him on what he knew about $3.6bn bonuses paid at Merrill Lynch in December, and related topics.

The visit to the offices of Andrew Cuomo, New York attorney-general, comes at a difficult time for Mr Lewis, who has spent two weeks jousting with lawmakers about bank nationalisation, and enduring criticism that he paid too much for Merrill Lynch, acquired by BofA on January 1.