WASHINGTON, Dec 3 (Reuters) - The U.S. Senate on Thursday confirmed Christopher Waller to the Federal Reserve's Board of Governors, giving him a voice on the central bank's policy-setting panel at a critical time in the nation's economic history.

Waller is the St. Louis Fed's research director and would be the fifth pick of outgoing President Donald Trump for the Board of Governors, whose members sit on the U.S. central bank's policy-setting committee.

The Fed cut interest rates to near zero as the coronavirus spread in March and has promised to keep them there until the labor market has healed and inflation has risen to its 2% goal. The Fed is also supporting the economy by buying $120 billion in Treasuries and mortgage-backed securities each month.

It is unclear if Waller will be sworn in before the central bank's next policy meeting, which starts in 12 days and at which policymakers will need to decide what, if any changes, they will make to the Fed's asset purchase program.

Waller's current boss, St. Louis Fed President James Bullard, is a big supporter of the central bank's current easy policy, and is among its more bullish policymakers as far as the economic outlook.

Michelle Bowman, the most recent addition to the Fed's Board of Governors, was sworn in 11 days after her confirmation vote.

Trump, who will be succeeded by President-elect Joe Biden on Jan. 20, had also nominated his former economic adviser, Judy Shelton, to the Fed board. But last month she failed to win enough support from the Republican majority in the Senate to move her confirmation forward, and no new vote has been scheduled. (Reporting by Ann Saphir and Richard Cowan Editing by Paul Simao)