President Trump on Thursday went on a lengthy rant about Federal Reserve Chair Jerome Powell, calling him a “numbskull” and suggested he may step in to “force something” on the Federal Reserve, but was short on details on what that might entail.

The president, while speaking to lawmakers and other attendees at a bill signing in the East Room to reverse California’s emissions rules, reiterated his call for Powell to lower rates and addressed firing the Fed chair who he first appointed in 2017.

“The fake news is saying ‘oh, if you fired him, it would be so bad. It would be so bad.’ I don’t know why it would be so bad. But I’m not going to fire him. I just want him to—you know, we call him ‘too late,’” Trump said, referring to a label he’s used for Powell related to his belief that Powell should have already lowered rates.

“We’ve got a lot of press. We’ve got a lot of cameras rolling right now, not that I like doing it ’cause I don’t. But if we take, if we cut our interest by one point, for years we save $300 billion. If we cut it by two points we save… $600 billion a year, $600 billion because of one numbskill that sits here, ‘I don’t see enough reason to cut the rates’ no,” Trump continued.

Trump added that during  his meeting with Powell last month, Trump told Powell he should lower rates for now. Trump  said he would support an increase in rates only if inflation were to rise again. 

Trump then suggested that he may “force something” when it comes to the Federal Reserve but he did not indicate whether that meant he was still considering firing Powell or if that referred to a mechanism for the president to act on interest rates. 

“I may have to force something,” the president said. “Somebody said, ‘who’s the genius who thought of that?’ I said, ‘it’s me’… but, I had an idea, I gave it. They said, ‘this is really— we’ll go short term for a year, let this guy get out of office, somebody will come in and cut it a couple of points.’”

“What is he doing? Why doesn’t he lower these rates?” he added.

Trump has been publicly critical over the central bank’s decision to hold interest rates steady even as inflation has cooled slightly. He also repeatedly bashes Powell, telling reporters last month that potentially meeting with him would be “like talking to a wall.”

Meanwhile, the Fed chair has defended not reducing rates as the Fed waits to see how the president’s whipsaw trade policies and tax cut plans affect a sturdy U.S. economy.