House Republican Conference Chairwoman Liz Cheney said Wednesday that President Trump made it clear to lawmakers in a Tuesday meeting that he'd let the government shut down if Congress doesn't approve $5 billion for the border wall.

"The president is not willing to give on this," Cheney, R-Wyo., said on Fox News. "He's been very firm, and we've go to get the $5 billion."

Cheney said that in their meeting with Trump Tuesday, Trump didn't offer a workaround if the money isn't approved.

"No," Cheney said when asked if there's a Plan B. "The plan is, we've got to get $5 billion for the wall."

She predicted that the showdown would put more pressure on Democrats to change their position, since most Americans support tough border security.

"The Democrats ... are in a tough spot," she said. "They want to abolish ICE, they want to have open borders. The American people are watching the kind of crime that that would result in, in terms of people flooding across our border."

Trump told Politico in an interview that he is "totally" willing to shut down the government over the wall, and Cheney said he told lawmakers the same thing in private.

"The president's been clear that he's willing to shut down the government if we don't get this $5 billion," she said.