President Trump suggested Saturday he was prepared to shut down the federal government next month if Congress fails to give him the money he wants to build a wall along the U.S. border with Mexico.

“If I was ever going to do a shutdown over border security – when you look at the caravan, when you look at the mess, when you look at the people coming in,” the president said. “… This would be a very good time to do a shutdown.”

The president has asked lawmakers for $5 billion for new wall construction in fiscal 2019, but Democrats oppose the project and a bipartisan Senate compromise earlier this year included just $1.6 billion for it.

During the 2016 campaign, Trump repeatedly promised voters that Mexico would pay for the roughly 2,000-mile barrier, which carries an estimated price tag of $20 billion. But since taking office, he has acknowledged that American taxpayers will have to put up the cash.

Speaking to reporters before traveling to California to tour recent wildfire devastation, Trump predicted Democrats would stave off his shutdown threat by agreeing to wall funding.

“I don’t think it’s going to be necessary, because I think the Democrats will come to their senses. And if they don’t come to their senses, we will continue to win elections,” the president said, referring to the Republicans’ success in adding to their Senate majority in congressional elections earlier this month.

Funding for the Department of Homeland Security and several other agencies runs out on Dec. 7, meaning a partial government shutdown will occur if a new spending bill is not finalized by then.

Most federal departments, including the Pentagon, are funded through the current fiscal year, which ends Sept. 30. But even a partial shutdown of other government activities next month would mean disrupted services as well as unpaid furloughs for thousands of federal workers amid the holiday shopping season.

The president’s willingness to shutter the government is not shared by Republican leaders on Capitol Hill. Senate Majority Leader Mitch McConnell of Kentucky said flatly last week, “No, we’re not going to do that,” when asked about prospects for a shutdown over wall funding.