Donald Trump has stormed out of a meeting with Democratic leaders, branding it a "total waste of time", after they again refused to fund his border wall.
The US president met with Senate Democratic leader Chuck Schumer and House Speaker Nancy Pelosi at the White House on Wednesday for talks hoping to end the partial government shutdown.
But after no progress was made, Mr Trump walked out before taking to Twitter.
He wrote: "I asked what is going to happen in 30 days if I quickly open things up, are you going to approve Border Security which includes a Wall or Steel Barrier? Nancy said, NO. I said bye-bye, nothing else works!"
New York Senator Chuck Schumer said that Mr Trump had asked Mrs Pelosi if she would agree to fund his wall.
He told reporters that when she refused, the president got up and said "then we have nothing to discuss, and he just walked out".
Mr Schumer added: "Again, we saw a temper tantrum because he couldn't get his way."
Mr Trump wants $5.7 billion to fund the wall.
He said earlier on Wednesday that he had a right to declare a national emergency to build a wall on the southern border if no deal with Congress can be reached.
He also threatened to withhold money to help California cope with wildfires, again suggested poor forest management is to blame for California's deadly wildfires.
Democrats plan to test Republicans' resolve on the issue by advancing a bill to immediately reopen the Treasury Department, the Securities and Exchange Commission and several other agencies that have been partially shut down since Dec. 22.
A shutdown of about a quarter of the US government reached its 19th day today, with lawmakers and the White House divided over President Trump's demand for money for a border wall ahead of his prime-time address to push the project.
The shutdown, which began on December 22, is the 19th since the mid-1970s, although most have been brief.
This one now ranks as the second longest, with Mr Trump saying it could continue for months or years, even as he said he hoped it would be resolved within days.
Border security negotiations last weekend between Vice President Mike Pence and congressional staff yielded no progress on a deal as Democrats continued to object to the wall.
The current shutdown has not affected three-quarters of the government, including the Department of Defense and the Postal Service, which have secure funding.
But 800,000 employees from the departments of Homeland Security and Transportation, among others, have been furloughed or are working without pay.
