DAVOS, Switzerland, Jan 21 (Reuters) - U.S. President Donald Trump said he has interviewed several strong candidates for Federal Reserve chair, but complained that nominees tend to change once they take office.

"Everyone ‌that I interviewed is great. Everyone could do, I think, a fantastic ​job. Problem is they change once they get the ‍job," Trump said at the World Economic ⁠Forum in ⁠Davos, Switzerland.

The president also renewed his criticism of current Federal Reserve Chair ‌Jerome Powell for not lowering ​interest rates fast enough and said an announcement on the next Fed chair is ⁠coming soon.

"I'll be announcing a ‍new ​Fed chairman in the not too distant future. I think he'll do a very good job. See, ‍I gave away some of it," Trump said.

The leading four candidates to succeed Powell are Trump economic adviser Kevin Hassett, Fed Governor Christopher Waller, former Fed Governor Kevin Warsh and BlackRock's chief bond investment manager, ​Rick ‍Rieder. On Tuesday, Treasury Secretary Scott Bessent said the president has whittled down the field to ​four candidates.

Trump and Bessent have repeatedly taken aim at Powell over his handling of monetary policy and interest rates, as well as his broader leadership of the Federal Reserve.

More recently, the Justice Department has issued a subpoena to Powell tied ​to the renovation of the Fed's headquarters.

Trump nominated Powell for the position in 2017, and former President Joe Biden reappointed him.