WASHINGTON — President Trump is ramping up his efforts to make a public case for his border wall, with the partial government shutdown now in its third week, planning a prime-time address Tuesday night and a visit to the U.S.-Mexico border Thursday.

Trump announced the news of the presidential address Monday on Twitter.

“I am pleased to inform you that I will Address the Nation on the Humanitarian and National Security crisis on our Southern Border,” he said. “Tuesday night at 9:00 P.M. Eastern.”

Earlier Monday, White House press secretary Sarah Sanders announced that Trump will go to the border with Mexico on Thursday.

“President @realDonaldTrump will travel to the Southern border on Thursday to meet with those on the frontlines of the national security and humanitarian crisis,” she said. “More details will be announced soon.”

The presidential speech and visit come amid the partial government shutdown and Trump’s insistence that any funding bill to reopen federal agencies include $5.7 billion for his border wall.

They also come three weeks before Trump’s State of the Union address, scheduled for Jan. 29.

As of 7 p.m. EST on Monday, CBS, NBC, ABC, CNN, Fox News and Fox Business Network had confirmed that they will carry Trump’s speech, which is expected to run about eight minutes. The Fox broadcast network did not respond to a request for comment.

In a joint statement Monday night, House Speaker Nancy Pelosi, D-Calif., and Senate Minority Leader Charles Schumer said Democrats deserve airtime as well to rebut the president’s message.

“Now that the television networks have decided to air the President’s address, which if his past statements are any indication will be full of malice and misinformation, Democrats must immediately be given equal airtime,” they said.

Before Trump’s speech from the Oval Office, Vice President Pence and Homeland Security Secretary Kirstjen Nielsen will meet with House Republicans on Capitol Hill early Tuesday evening to discuss the border situation, according to two House Republican aides.

Pence told reporters Monday that Trump has invited Democrats back to the White House this week for further talks.

“Our position is very simply this: There is a humanitarian and national security crisis at the southern border,” Pence said during a briefing in the Eisenhower Executive Office Building. He said that the White House has “been negotiating to open the government and address that border crisis” as well as “taking steps to mitigate the effects of the shutdown.”

Some Democrats responded to the news of Trump’s address with concern that he would mislead the American people about the situation at the border.

“I expect the president to lie to the American people,” House Judiciary Committee Chairman Jerrold Nadler (D-N.Y.) said. “Why do I expect this? Because he has been lying to the American people.”

Nadler was part of a delegation of Democratic lawmakers who toured a Border Patrol facility in Alamogordo, New Mexico, on Monday to investigate the death of 8-year-old Felipe Gomez Alonzo, the second child to die in December after being apprehended crossing the border illegally.

Trump made his first visit to the border as president 10 months ago. During that trip, Trump toured 30-foot-tall steel and concrete prototypes of the border wall in California and strongly condemned jurisdictions that offer “sanctuary” to undocumented immigrants.

The White House did not immediately release details Monday on the site of Trump’s planned visit. But the Federal Aviation Administration issued a notice that airspace in the McAllen, Texas, vicinity would be restricted Thursday due to a “VIP movement.”

The border city of 142,000 people is home to a U.S. Customs and Border Protection facility where migrants who have crossed illegally into the country have been detained. First lady Melania Trump also visited a shelter for migrant children in McAllen in June.

Trump and congressional Democrats remain at an impasse on crafting a deal to reopen the government, which is in its 17th day of a partial shutdown. Democrats, who retook control of the House last week, have passed measures that would fund the federal agencies affected, but Trump has balked at any legislation that does not meet his demand for border wall funding.

Tuesday’s speech shapes up as both a policy issue and a political stunt – an attempt by the president to persuade the public that his vision of a border wall trumps Democratic opposition to it.

As such, the White House’s request for airtime is more problematic than other kinds of presidential addresses, such as a response to a national defense emergency, an economic crisis or the annual State of the Union speech.

The networks also have to balance their obligation to inform viewers about current affairs versus their desire not to preempt lucrative prime-time entertainment programs for the speech.

In fact, the broadcast networks – ABC, CBS, Fox and NBC – didn’t show President Obama’s immigration speech in November 2014, when he outlined changes in immigration policy. That speech was delivered during a “sweeps” month, in which ratings for prime-time programs are used to set future ad prices.

While the broadcast networks typically carry presidential addresses, there is no requirement or regulation compelling them to do so. “This isn’t state television,” in which authorities control the airwaves, said Andrew Jay Schwartzman, a veteran communications attorney at the Georgetown University Law Center.

Nor are the networks’ hundreds of affiliated local stations required to air programs distributed by their network partners. On the other hand, they can choose to air a presidential speech even if their affiliated network isn’t airing it.

A spokesman for the National Association of Broadcasters, which represents local stations, said “traditionally and typically” networks and stations will carry a presidential address “since we are committed to our role as first informers.”

As the new Congress convened, Pence called House Republicans last week and urged them to vote against Democratic measures that would have reopened the government without wall funding.

Tuesday’s meeting comes ahead of votes that Pelosi has planned on a piecemeal reopening of the government, beginning with the Treasury Department and the Internal Revenue Service.

This week’s votes will put Republicans in a particularly challenging spot, as they will spotlight the issue of whether millions of Americans get their tax refund checks.

In a sign that the Trump administration is worried about a potential public backlash on the issue, the White House decided Monday that it is legally permissible to process tax returns during the shutdown, reversing past IRS policy.

Yet talks between the White House and congressional aides over the weekend showed no signs of a breakthrough, and hundreds of thousands of federal workers remain furloughed.

Tony Reardon, president of the National Treasury Employees Union, said in an appearance on MSNBC on Monday that federal employees “have really been kicked into the middle of a political fight that they didn’t create and that they don’t have the authority to try and resolve.”

“This has gone way too far,” said Reardon, whose union represents 150,000 members at 33 federal agencies and departments. “Get these people back to work and get them paid.”

Trump said Sunday that he understood the predicament facing federal workers who are not receiving their paychecks.

“I can relate, and I’m sure the people who are on the receiving end will make adjustments; they always do,” he told reporters outside the White House