NEW YORK - US President Donald Trump on Tuesday accused the Federal Reserve of not being bullish in lowering interest rates.

Trump made the accusation in a speech to the Detroit Economic Club in Detroit, local media reported.

In an interview with the CBS Evening News later on Tuesday night, Trump said Fed Chair Jerome Powell is "either corrupt or incompetent".

When asked if the Justice Department's criminal investigation of Powell appeared to be political retribution as Powell has resisted Trump's repeated pressure to lower interest rates, Trump said, "I can't help what it looks like."

The Fed confirmed late Sunday that the federal prosecutors are investigating Powell over the central bank's multi-billion-dollar project to renovate its headquarters.

"The threat of criminal charges is a consequence of the Federal Reserve setting interest rates based on our best assessment of what will serve the public, rather than following the preferences of the President," Powell said in a public statement on Sunday.

Also on Tuesday, The Wall Street Journal reported that Trump slammed a group of US attorneys for not moving fast enough to prosecute his favored targets during an event at the White House last week.

Dozens of attorneys from across the United States gathered at the White House on Thursday for a ceremonial photo shoot before Trump criticized them for being ineffective and for disrupting the work of Attorney General Pam Bondi and her deputy, Todd Blanche, the report said, citing people familiar with the exchange.