BofA's Ken Lewis to Retire at Year's End

Updated from 1:14 a.m. EDT.

CHARLOTTE, N.C. (TheStreet) -- Bank of America(BAC) said Ken Lewis, its CEO since 2001, has decided to retire at the end of the year.

The surprising announcement late Wednesday comes after Lewis guided the nation's largest bank through the financial crisis of the past year, including a controversial combination with Merrill Lynch. Bank of America required $45 billion in TARP funds to survive the turmoil, however, and it's now facing considerable scrutiny about its disclosure of bonuses paid and losses incurred by Merrill ahead of shareholder approval of the acquisition.

The company said its board would "continue ongoing planning" in order to name a successor by the time Lewis steps down on Dec. 31. Lewis is also leaving his position as a director on the company's board.

Lewis, 62, cited a number of reasons for the timing of his announcement.

"Bank of America is well positioned to meet the continuing challenges of the economy and markets," Lewis said in a statement. "I am particularly heartened by the results that are emerging from the decisions and initiatives of the difficult past year-and-a-half."

Of the company's acquisitions of Merrill Lynch and Countrywide, Lewis said the integrations of those operations were "on track and returning value already." He added that the company was "in position to begin to repay the federal government's TARP investments."

Lewis has come under fire in recent months for his role in steering the bank's acquisition of Merrill last fall. Irate shareholders in April voted to strip him of his chairman title, and longtime director Walter Massey assumed the mantle.