WASHINGTON (AP) — President Donald Trump stalked out of his negotiating meeting with congressional leaders Wednesday — "I said bye-bye," he tweeted soon after — as efforts to end the 19-day partial government shutdown fell into deeper disarray over his demand for billions of dollars to build a wall on the U.S.-Mexico border. Hundreds of thousands of federal workers now face lost paychecks on Friday.

The president is to visit the border in person on Thursday, but he has expressed his own doubts that his appearance and remarks will change any minds.

The brief session in the White House Situation Room ended almost as soon as it began.

Democrats said they asked Trump to re-open the government but he told them if he did they wouldn't give him money for the wall that has been his signature promise since his presidential campaign two years ago.

Republicans said Trump posed a direct question to House Speaker Nancy Pelosi: If he opened the government would she fund the wall? She said no.

Senate Democratic leader Chuck Schumer said Trump slammed his hand on the table and walked out. Republicans said Trump, who passed out candy at the start of the meeting, did not raise his voice and there was no table pounding.

One result was certain: The shutdown plunged into new territory with no endgame in sight. The Democrats see the idea of the long, impenetrable wall as ineffective and even immoral, a terrible use of the $5.7 billion Trump is asking. He sees it as an absolute necessity to stop what he calls a crisis of illegal immigration, drug-smuggling and human trafficking at the border.

"The president made clear today that he is going to stand firm to achieve his priorities to build a wall -- a steel barrier -- at the southern border," Vice President Mike Pence told reporters afterward.

That insistence and Trump's walking out were "really, really unfortunate," said Schumer.

Trump had just returned from Capitol Hill where he urged jittery congressional Republicans to hold firm with him. He suggested a deal for his border wall might be getting closer, but he also said the shutdown would last "whatever it takes."

He discussed the possibility of a sweeping immigration compromise with Democrats to protect some immigrants from deportation but provided no clear strategy or timeline for resolving the standoff, according to senators in the private session. He left the Republican lunch boasting of "a very, very unified party," but GOP senators are publicly uneasy as the standoff ripples across the lives of Americans and interrupts the economy.

Trump insisted at the White House "I didn't want this fight." But it was his sudden rejection of a bipartisan spending bill late last month that blindsided leaders in Congress, including Republican allies, now seeking a resolution to the shutdown.

GOP unity was being tested further late Wednesday with the House voting on a bipartisan bill to reopen one shuttered department, Treasury, to ensure that tax refunds and other financial services continue. Republicans were expected to join Democrats in voting, defying the plea to stay with the White House.

Ahead of his visit to Capitol Hill, Trump renewed his notice that he might declare a national emergency and try to authorize the wall on his own if Congress won't approve the money he's asking.

"I think we might work a deal, and if we don't I might go that route," he said.

There's growing concern about the toll the shutdown is taking on everyday Americans, including disruptions in payments to farmers and trouble for home buyers who are seeking government-backed mortgage loans — "serious stuff," according to Sen. John Thune, the No. 2 Senate Republican.

Sen. Lisa Murkowski, R-Alaska, was among several senators who questioned Trump at the Capitol.

"I addressed the things that are very local to us -- it's not just those who don't receive a federal paycheck perhaps on Friday but there are other consequences," she said, mentioning the inability to certify weight scales for selling fish. The president's response? "He urged unity."

Sen. John Cornyn, R-Texas, said "the president thinks there will be increasing pressure on everybody to come to the table once people start missing their paycheck."

Earlier, Cornyn called the standoff "completely unnecessary and contrived. People expect their government to work. ... This obviously is not working."

Like other Republicans, Sen. Shelley Moore Capito of West Virginia said she wants border security. But she said there was "no way" the shutdown fight would drag on for years as Trump warned last week.

"I think certainly I have expressed more than a few times the frustrations with a government shutdown and how useless it is," Capito said Tuesday. "That pressure is going to build."

Democrats said before the White House meeting that they would ask Trump to accept an earlier bipartisan bill that had money for border security but not the wall. Pelosi warned that the effects of hundreds of thousands of lost paychecks would begin to ripple across the economy.

"The president could end the Trump shutdown and re-open the government today, and he should," Pelosi said.

But the meeting breakup put an end to that idea.

Tuesday night, speaking to the nation from the Oval Office for the first time, Trump argued that the wall was needed to resolve a security and humanitarian "crisis." He blamed illegal immigration for what he said was a scourge of drugs and violence in the U.S. and asked:  "How much more American blood must we shed before Congress does its job?"

Democrats in response accused Trump appealing to "fear, not facts" and manufacturing a border crisis for political gain.

A growing number of Republicans are uncomfortable with the toll the partial shutdown is taking, and Trump's response to it. They are particularly concerned about the administration's talk of possibly declaring a national emergency at the border, seeing that as an unprecedented claim on the right of Congress to allocate funding except in the most dire circumstances.

"I prefer that we get this resolved the old-fashioned way," Thune said.

Trump did not mention the idea of a national emergency declaration Tuesday night. A person unauthorized to discuss the situation said additional "creative options" were being considered, including shifting money from other accounts or tapping other executive authorities for the wall.

Trump on Wednesday floated ideas that have been circulated for a broader immigration overhaul. Trump ally Sen. Lindsey Graham has suggested a compromise that would include wall funding as well as protecting some immigrants from deportation.

In their own televised remarks, Pelosi and Senate Minority Leader Chuck Schumer accused Trump of misrepresenting the situation on the border as they urged him to reopen closed government departments and turn loose paychecks for federal workers.

Negotiations on wall funding could proceed in the meantime, they said.

Schumer said Trump "just used the backdrop of the Oval Office to manufacture a crisis, stoke fear and divert attention from the turmoil in his administration."

In an off-the-record lunch with television anchors ahead of his speech, Trump suggested his aides had pushed him to give the address and travel to the border and that he personally did not believe either would make a difference, according to two people familiar with the meeting. But one person said it was unclear whether Trump was serious or joking.

The people familiar with the meeting insisted on anonymity because they were not authorized to discuss the meeting publicly.

___

Associated Press writers Jill Colvin, Colleen Long, Alan Fram and Deb Riechmann contributed to this report.

For AP's complete coverage of the U.S. government shutdown: https://apnews.com/GovernmentShutdown