President Donald Trump is visiting the US-Mexico border in a bid to bolster his case for a wall after talks with Democrats ended in acrimony.
Mr Trump stormed out of his meeting with congressional leaders as efforts to end the partial government shutdown fell into deeper disarray.
Hundreds of thousands of federal workers will not be paid again on Friday.
“The Opposition Party & the Dems know we must have Strong Border Security, but don’t want to give ‘Trump’ another one of many wins!” Mr Trump tweeted on Thursday before departing for Texas.
During his stop in McAllen, Mr Trump will visit a border patrol station for a discussion on immigration and border security.
But Mr Trump has expressed his own doubts that his appearance and remarks will change any minds, as he seeks 5.7 billion dollars for the wall that has been his signature promise since his presidential campaign.
McAllen is located in the Rio Grande Valley, the busiest part of the border for illegal border crossings.
The unravelling talks prompted further speculation about whether Mr Trump would declare a national emergency and try to authorise the wall on his own if Congress will not approve the money he is seeking.
Before leaving for Texas, he told reporters it would be “very surprising” for him not to declare a national emergency if he cannot reach a deal with Democrats over funding.
He said he would prefer to work with Congress on a deal to end the partial government shutdown and is open to compromise but will use his emergency powers to circumvent Congress if they cannot come to agreement.
He said: “We have to get a win … or I will declare a national emergency.”
He also defended his repeated claims that Mexico will pay for his wall — even when Mexico has said it will not.
Mr Trump said he “never said they were going to write out a cheque” and would pay for it indirectly “many, many times over”.
The White House meeting in the Situation Room on Wednesday ended after just 14 minutes.
Democrats said they asked Mr Trump to reopen the government but that he told them if he did they would not give him money for the wall.
Republicans said Mr Trump posed a direct question to House Speaker Nancy Pelosi – if he opened the government, would she fund the wall and she said no.
Senate Democratic leader Chuck Schumer said Mr Trump slammed his hand on the table. However, Republicans said Mr Trump, who handed out sweets at the start of the meeting, did not raise his voice and there was no table pounding.