Speaking to a room filled with congressional Republicans in Washington, President Donald Trump on Tuesday criticized members of his party trying to pull back his tariff authority.

“I’m telling you, these countries are calling us up,” Trump said at a National Republican Congressional Committee dinner. “They are dying to make a deal.”

“And then I’ll see some rebel Republican, you know, some guy that wants to grandstand, say, ‘I think that Congress should take over negotiations.’ Let me tell you, you don’t negotiate like I negotiate.”

“We have to remain united,” he added.