President Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE on Thursday insisted that Congress must grant his request for money to build a border wall, despite mounting pressure to end the record-long government shutdown.

“The federal government remains shut down because congressional Democrats refuse to approve border security,” Trump said. “We are going to have powerful, strong border security.”

ADVERTISEMENT

In remarks at the Pentagon focused on missile defense, Trump took aim at Speaker Nancy Pelosi Nancy PelosiPelosi: Ginsburg successor must uphold commitment to 'equality, opportunity and justice for all' Bipartisan praise pours in after Ginsburg's death Pelosi orders Capitol flags at half-staff to honor Ginsburg MORE (D-Calif.) and accused her of refusing to allow moderate Democrats to negotiate over his demand for $5.7 billion in wall funding.

The president did not address Pelosi’s request to reschedule his Jan. 29 State of the Union address, a move that raised the stakes in the standoff between the two leaders.

Speaking to reporters in the Capitol before Trump’s speech, Pelosi appeared surprised that the president — known for hitting back at critics — had not responded to her request made Wednesday morning.

“We haven’t heard. Very silent, more than 24 hours,” she said.

White House officials said Wednesday they felt no rush to respond to Pelosi’s letter, which did not formally rescind her invitation to the president to speak.

Democrats have repeatedly dismissed the president’s request and demanded the government reopen before resuming negotiations on border security.

“The party has been hijacked by the open-borders fringe within the party,” Trump said Thursday. “The radical left becoming the radical Democrats. Hopefully, Democrat lawmakers will step forward to do what is right for our country.”

The president met with a group of centrist Democrats at the White House on Wednesday, but the discussion produced no breakthrough as members urged him to end the shutdown.

Trump’s defiant statement is the latest signal the partial shutdown, which has entered its 27th day, has no end in sight.

Trump is also facing pressure, however, from some White House advisers and Republicans in Congress who want him to end the shutdown, which is beginning to take a toll on the 800,000 federal workers who are going without paychecks and beyond.

An internal White House study showed a prolonged shutdown could eventually push the U.S. into an economic contraction, according to The New York Times.

Mike Lillis contributed.