Washington (CNN) President Donald Trump isn't doing Congress any favors when it comes to figuring out how to avoid a partial government shutdown in nine days.

"I don't know what his plan is," John Cornyn, the No. 2 Senate Republican, told CNN Thursday, as Congress searches for a budget resolution that appeases both Trump and the handful of Senate Democrats needed for passage.

On Tuesday, the President clashed with Democratic leaders over $5 billion in funding a US-Mexico border wall he said he wants as part of an agreement to keep the government open. Even though his party still retains control of Congress until the end of the year, Senate Democratic votes are needed to pass a budget.

But on Thursday morning, Trump said the new US trade agreement with Mexico and Canada would be the source of the wall's funding.

"I often stated, 'One way or the other, Mexico is going to pay for the Wall.' This has never changed. Our new deal with Mexico (and Canada), the USMCA, is so much better than the old, very costly & anti-USA NAFTA deal, that just by the money we save, MEXICO IS PAYING FOR THE WALL!" Trump tweeted Thursday morning.

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