President Donald Trump on Sunday threatened to shut down the federal government this fall unless Democrats give in to his border security demands, including by giving him billions more for his proposed southern border wall.

Should Democrats continue denying Trump his border barrier and other demands and the president make good on his high-stakes threat, it would be the third funding lapse of his tenure. It also would shutter the government just weeks before voters will decide which party controls the House and Senate — and the Trump-GOP agenda — come January.

“I would be willing to “shut down” government if the Democrats do not give us the votes for Border Security, which includes the Wall!” he wrote.

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Trump called for lawmakers to send him a bill that ends the visa lottery system and the policy known as “catch-and-release,” meaning detaining undocumented migrants and releasing them into the country while they await a court hearing. He also seemed to make his long-stated call for an “Immigration [system] based on MERIT!” a requirement to keep the government operating this fall.