Fed's Williams under consideration for No. 2 Fed post: WSJ

A San Francisco Fed spokesman declined to comment to Reuters. The Wall Street Journal said it was unclear whether Williams is a front runner.

Williams said he would welcome such an opportunity to be the vice chair, the Financial Times reported. http://on.ft.com/2DnIhzb

"Of course I welcome opportunities to contribute at the highest level I can if that would help us do our work," he told FT in a statement.

Williams would serve under Jerome Powell, a Fed governor who is to become the Fed chair early next month, succeeding Janet Yellen.

Williams, who holds a doctorate in economics and whose research on monetary policy and interest rates has been influential both inside and outside the U.S. central bank, would be part of the trio of policymakers at the centre of U.S. rate-setting that traditionally includes the Fed chair, the vice chair and the chief of the New York Fed.

The Fed Board's former No. 2, Stanley Fischer, who was also a highly regarded economist and central banker, retired late last year.

William Dudley, the current president of the New York Fed and who is also an economist, plans to step down in mid-2018, and the bank is in the midst of a search for his replacement. The heads of the Federal Reserve regional banks are appointed by each bank's board. The members of the Fed Board in Washington are named by the U.S. president, subject to Senate confirmation.

Powell has deep experience in financial markets and has been a Fed governor for five years, but he has no academic background in economics.

Williams took the top job at the San Francisco Fed in 2011, succeeding Yellen after President Barack Obama named her as the Fed's vice chair under Ben Bernanke, a post she held until she succeeded Bernanke as chair in 2014.

Williams had been her director of research at the San Francisco Fed.

(Reporting by Ann Saphir; Additional reporting by Kanishka Singh in Bengaluru; Editing by James Dalgleish and Leslie Adler)