He told reporters: "Listen, anything can happen".
Senate Democratic leader Chuck Schumer voted for the Secure Fence Act, which passed the Senate on an 80-19 vote. That meeting ended after 30 minutes with no resolution.
"We've insisted on 5 for the discussions", Mulvaney, who is also the incoming acting White House chief of staff, said in a separate appearance Sunday on ABC's "This Week".
Meanwhile, from coast to coast, the first day of the shutdown played out. No votes were scheduled, and House and Senate members were told they would receive 24 hours' notice before any vote.
Before Pence and Schumer met today, Schumer's office sent out a pre-emptive statement beforehand saying he would "remind" Pence that Democrats would not sign off on any wall funding.
"When everybody leaves town, it takes the pressure off for a deal", said New York Representative Lee Zeldin, a Republican, one of the few lawmakers lingering in the Capitol on Sunday.
His latest - no joke: "I am all alone (poor me) in the White House", as he attacks Democrats for the shutdown he proudly boasted he would not only cause, but take credit for.
The shutdown has affected thousands of federal employees.
Both sides spent Saturday dug into their positions over the terms of reopening the nine government departments whose funding expired after Friday night.
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It's a good decision to stay in charge of the game, and second half we could do that again. I am completely happy with the result and it is big for us.
Britain's Gatwick airport reopens after 6-hour shutdown over reports of drones
The airport said it was investigating the incident and apologised to customers for the inconvenience after the runway was closed. Under British legislation, drones can not be flown near aircraft or airports, or at an altitude of over 400 feet (122 metres).
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Keeping in line with the couple's continued blending of cultures, Jonas wore a traditional tailored suit in navy blue. Jonas and the 36-year-old Chopra have been celebrating their wedding all month and honoring both of their cultures.
Democrats are staunchly opposed, and in the absence of a deal, federal funds for dozens of agencies lapsed. The Securities and Exchange Commission has posted a list of the services it will soon suspend, including the processing of certain business records.
Customs and border staff will keep working, although their pay will be delayed. Chris Van Hollen and Ben Cardin, who represent Maryland, where many DC-area federal employees live.
Trump was also referring to a far more ambitious 2006 Senate bill that passed by an 80 to 19 margin.
Trump is demanding US$5 billion, but congressional Democrats are refusing to accede in a stalemate that provides a chaotic coda for Republicans in the waning days of their two-year reign controlling the government.
We saw some folks are raising money for a border wall to keep out our migrant siblings and fellow human beings, who are fleeing violence and persecution and whose tragically-underpaid labor is essential to the USA economy.
A shutdown results from an impasse in the USA government when Republicans and Democrats can't agree on what should be included in the latest spending bill.
Mulvaney countered that "the president's not going to not accept money for a border wall". "The president wanted the shutdown, but he seems not to know how to get himself out of it". No such grand deal is on the table now. "General Mattis did not see this as a problem", Trump said. "We arrived at this moment because President Trump has been on a destructive two-week temper tantrum". The comments highlighted Trump's unpredictable negotiating style.
"We moved off of the five and we hope they move up from their 1.3", Mulvaney said.