President Donald Trump has announced he could declare a national emergency in order to build the Mexican border wall without the approval of Congress.
The announcement came after the president met senior Democrats, who refused his requests for funding.
The stand-off has seen President Trump withhold support for a bill to fully fund the government until he gets money for the border wall.
Donald Trump said he was prepared for the partial government shutdown – now in its third week – to last years.
Around 800,000 federal workers have been without pay since December 22.
President Trump’s aides and lawmakers will meet on January 5 in a fresh bid to resolve the impasse.
Oval Office Battle: President Trump Clashes with Chuck Schumer and Nancy Pelosi over Border Wall Funding
The president initially gave a positive account of the 90-minute meeting at the White House, describing it as “very productive”.
However, when asked whether he had considered using emergency presidential powers to bypass congressional approval of funding, President Trump said he had.
He said: “I may do it. We can call a national emergency and build it very quickly. That’s another way of doing it.”
“I’m very proud of doing what I’m doing,” President Trump added.
“I don’t call it a shutdown, I call it doing what you have to do for the benefit and safety of our country.”
On January 4, House Speaker Nancy Pelosi said the meeting had been “contentious”, while Senate Democratic leader Chuck Schumer said: “We told the president we needed the government open. He resisted.”
Democrats, who now hold the majority in the House, passed spending bills on January 3 to reopen the government, including $1.3 billion of border security funds until February 8.
However, the legislation cannot take effect unless it passes the Republican-controlled Senate, where leader Mitch McConnell said his party would not back any measure without President Trump’s support.