Republican leaders expect President Trump to veto a measure attempting to overturn his declaration of a national emergency to enable construction of a wall along the U.S.-Mexico border, after the Senate votes on it this week.

The Senate’s third-highest ranking Republican, Sen. John Barrasso (Wyo.), said on Fox News’s “Sunday Morning Futures” that he had met with Trump “a couple of times” over the past week and that “he’s going to veto this, and his veto will be sustained.”

Barrasso’s comments are an effective admission that the GOP does not have the votes to prevent the full Senate from voting to annul Trump’s order, which many lawmakers say rips congressional authority away from them and threatens important military construction projects.

“There are projects there that take care of the men and women that keep us safe that are going to be impacted,” Rep. Will Hurd (R-Tex.) said on CNN’s “State of the Union.”

President Trump declared a national emergency to fund his border wall. Here are some of the challenges that could crop up to block his declaration. (Jenny Starrs/The Washington Post)

Such an emergency declaration, he noted, “goes against what our constitution has said.”

Even though Congress may have given the president certain budgeting authorities during times of emergency, “I think we need to call that back,” Hurd said.

Hurd was one of 13 Republicans who supported the effort to nullify Trump’s emergency declaration when the House voted on a similar measure last month that passed 245 to 182. That margin is not enough to overcome a presidential veto, however.

Trump has tried to dissuade Senate Republicans from supporting the measure, insisting in a tweet last week that “Senate Republicans are not voting on constitutionality or precedent, they are voting on desperately needed Border Security & the Wall.

“Our Country is being invaded with Drugs, Human Traffickers, & Criminals of all shapes and sizes. That’s what this vote is all about. STAY UNITED!”

With four Senate Republicans committed to supporting the Democrats’ resolution, it is clear that Trump will have to exercise his veto power to keep his emergency declaration and wall plans alive.

Few lawmakers on either side deny there is a problem at the border that the government must fix. But Trump’s critics, including many in the GOP, say that strategically deployed technology and monitoring, as well as a new approach to the processing of asylum cases, can do more to address the spike in arrivals of undocumented migrants at the southern border than any edifice Trump has proposed.

Even after the president goes above Congress to secure his emergency funds, a new fight is on the horizon, over a request for an additional $8.6 billion in wall funding that the administration is expected to make to Congress this week.

The money, which is part of the administration’s budget request for fiscal 2020, would be divided across the Homeland Security and Defense departments to aid the construction of a border wall. According to a senior administration official, the White House believes that money — combined with the funds Trump is able to redirect as a result of his emergency announcement — will let the government finish wall construction along 722 miles of the border, which has long been a White House goal.

But Democrats, who control the House, are not inclined to give Trump the money he wants as they hash out next year’s budget.

“President Trump hurt millions of Americans and caused widespread chaos when he recklessly shut down the government to try to get his expensive and ineffective wall,” House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.) said in a statement Sunday. “Congress refused to fund his wall and he was forced to admit defeat and reopen the government. The same thing will repeat itself if he tries this again. We hope he learned his lesson.”