WASHINGTON — With a partial government shutdown looming, White House and congressional Democrats are staring each other down from opposite sides of the border wall issue.

Senate Minority Leader Chuck Schumer, D-N.Y., and House Minority Leader Nancy Pelosi, D-Calif, warned Monday that negotiators could finish a budget bill by Friday, but only if U.S. President Donald Trump no longer insists on funding to build a wall on the U.S.-Mexico border.

In a joint conference call with reporters Monday, Schumer said Trump's request for border wall funding "threw a monkey wrench" into budget negotiations with Senate Majority Leader Mitch McConnell, R-Ky., and House Speaker Paul Ryan, R-Wis. — saying that "if the president stepped out of it, we could get a budget done by Friday."

"Before, parties were negotiating quite well — Leader Pelosi, myself, Speaker Ryan and Leader McConnell — until Donald Trump and the White House threw a monkey wrench into this, with the wall, which is not only unpopular with Democrats but with many Republicans who we've heard yesterday," Schumer said.

With the April 28 deadline to fund the federal government just days away, Pelosi upped the ante, warning that Democrats will not agree to a short-term continuing resolution to keep the government open unless a deal is in hand.

"The only justification for any extension, which I would hope we wouldn't need, would be just to take it to the floor," Pelosi said.

Administration officials were talking tough, as well. Attorney General Jeff Sessions said Monday that Democrats will be to blame if the government shuts down at the end of the week.

"It will be the Democrats who shut this government down to block the funding of the wall. That's what the question is. Are they going to shut the government down?" he said on the television show "Fox & Friends."

On Sunday, White House budget director Mick Mulvaney refused to rule out a veto if Congress fails to pass Trump's request, from March, for $1.5 billion to fund the wall.

"We are asking for our priorities," Mulvaney said on the Fox News show. "[W]hat I would say is that they're holding hostage national security. Again, something they've supported in the recent past when President [Barack] Obama was in the Senate. So we don't understand why this is breaking down like this."

Trump tweeted several times over the weekend on the issue, rapping Democrats for fighting the budget wall, "despite the fact that it will stop drugs and very bad MS 13 gang members."

But Schumer pointed to Republicans who have criticized the wall: Rep. Peter King, R-N.Y.; Sen. Marco Rubio, R-Fla.; and Sen. Lindsay Graham, R-S.C.

Rep. Tom Cole, R-Okla., said on MSNBC on Monday that Republicans should return to the issue later, adding that his party would be blamed for a shutdown. "I wouldn't risk a $1 trillion funding bill for a $3 million wall," he said.

"The most important thing is to make the sure military is funded, to make sure the critical institutions of government are funded and to make sure you don't have a shutdown while you've got a Republican president, a Republican Senate [and] a Republican House," Cole said.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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