WASHINGTON – Parts of the federal government will almost certainly remain closed through the holidays after the Senate adjourned on Saturday and made no plans to return until the middle of next week.

Senate Majority Leader Mitch McConnell, R-Ky., announced no other session is planned until Thursday, virtually guaranteeing that a partial government shutdown will continue through the holidays.

House and Senate lawmakers had returned to work Saturday as behind-the-scenes negotiations continued in hopes of ending a budget standoff. But by mid-afternoon, there were obvious signs that no deal was imminent.

Late Saturday, the White House announced that President Donald Trump had canceled an end-of-the year trip to southern Florida and would remain in Washington over the holidays. First Lady Melania Trump, already in Florida, planned to return to Washington so they could spend Christmas together, White House spokeswoman Sarah Huckabee Sanders said.

With the first day of the shutdown under way, Trump tweeted on Saturday that he was having lunch with a “large group” about border security, but it was mostly with supporters within Congress.

The White House later released the list of attendees, including Vice President Mike Pence and GOP Sens. Richard Shelby of Alabama, Lindsey Graham of South Carolina and Mike Lee of Utah. Republican Reps. Mark Meadows of North Carolina, Jim Jordan of Ohio, Matt Gaetz of Florida and Andy Biggs of Arizona – all members of the hard-line House Freedom Caucus – also were expected to attend. No Democratic lawmakers were on the list.

Parts of the federal government shut down Saturday - for the third time this year - after a last-ditch effort by Republicans and Democrats failed to resolve a budget stalemate.

Speaking on the Senate floor, Senate Majority Leader Mitch McConnell, R-Ky., said talks are continuing between Democrats and the White House. If an agreement can be reached, he said, it would be put to a vote in the Senate.

“We’ve pushed the pause button until the president … and Senate Democrats … reach an agreement,” he said. “No procedural votes. No test votes. Just a meaningful vote on a bipartisan agreement whenever that is reached.”

“It’s my hope that is reached sooner rather than later,” he added.

Senate Democrats, however, vowed they would not retreat from their opposition to funding for a border wall.

“President Trump, if you want to open the government, you must abandon the wall – plain and simple," Senate Minority Leader Chuck Schumer, D-N.Y., said from the Senate floor.

For now, no deal appeared to be in sight.

What is certain is that nine federal departments and several smaller agencies ran out of funding at midnight Friday, requiring them to close their doors, and put more than 380,000 federal workers on furlough and force another 420,000 employees to work without pay.

The good news is that only one-fourth of the government will be impacted by the shutdown because most federal agencies already have been funded by Congress.

The bad news is for those agencies who have not received funding beyond the midnight deadline. They include the FBI, the Bureau of Prisons, Customs and Border Patrol and the IRS, as well as national parks and forests. In all, the nine departments impacted by the shutdown are Agriculture, Commerce, Justice, Homeland Security, Interior, State, Transportation, Treasury and Housing and Urban Development.

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It was not clear how long the standoff would last, but Trump has said he is "totally prepared for a very long shutdown."

Late Saturday morning, Trump tweeted that he was in the White House talking about a solution to the impasse, but warned it could last awhile.

“We are negotiating with the Democrats on desperately needed Border Security (Gangs, Drugs, Human Trafficking & more) but it could be a long stay,” Trump tweeted.

Trump also complained about news coverage of the shutdown (as well as his decision to pull U.S. troops out of Syria).

On Friday, Trump sought to place the blame for the shutdown on Democrats, who refused to go along with his demand for $5 billion to build a wall along the nation’s southern border.

“The Democrats now own the shutdown!” he tweeted, marking a reversal from a week ago when he boasted that he’d be “proud” to shut down the government and would accept the blame.

“You will not get your wall,” Schumer shot back.

Schumer and other Democrats put the responsibility for the shutdown squarely on Trump, arguing that he had reneged on a promise to sign a short-term spending bill that would have funded the government through Feb. 8.

That bill, which passed the Senate, would have put off until next year a decision on border wall funding, drawing Trump’s ire and dooming the measure’s fate in the House.

A separate bill approved by the House also would have funded the government through Feb. 8 but would have provided $5.7 billion for a border wall and nearly $8 billion in disaster relief. That bill failed to get a vote in the Senate, essentially guaranteeing a government shutdown.

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