WASHINGTON — Senate Majority Leader Mitch McConnell cautioned President Trump privately this week about the consequences of declaring a national emergency to build his border wall, telling him the move could trigger political blowback and divide the Republican Party, according to two Republicans with knowledge of the exchange.

McConnell, R-Ky., told Trump that Congress might end up passing a resolution disapproving the emergency declaration, the people said – which would force the president to contemplate issuing his first veto ever, in face of opposition from his own party.

McConnell delivered the message during a face-to-face meeting with the president Tuesday at the White House, according to the Republicans, who requested anonymity to describe the encounter. The two men met alone, and conversed with no aides present. Their meeting was not publicly announced.

The majority leader’s comments to the president came amid rising GOP concerns over the fallout if Trump were to declare a national emergency that would allow him to circumvent Congress and use the military to build new walls along the U.S.-Mexico border. Trump increasingly appears prepared to go that route, saying Friday that “I think there’s a good chance we’ll have to do that.”

Trump teased the possibility of making a definitive statement on the topic during his State of the Union address, telling reporters to watch the Tuesday speech closely. “I think you’ll find it very exciting,” the president said.

And Trump again dismissed chances that he’ll get the $5.7 billion in wall funding he wants from a bipartisan congressional committee charged with producing a border security solution that could forestall another government shutdown. The committee is working to come up with a deal that could pass before Feb. 15, when a stopgap spending bill will expire absent action by Congress and Trump.

If that happens, large portions of the federal government that reopened Jan. 25 after a record-long funding lapse would shut down again.

“We will be looking at a national emergency because I don’t think anything’s going to happen,” Trump told reporters at the White House. “I don’t think Democrats want border security.”

The White House did not immediately return a request for comment on the meeting between McConnell and Trump. A McConnell spokesman declined to discuss the senator’s private conversations.

REPUBLICANS DIVIDED

On the same day he met with the president, McConnell publicly announced his opposition to a national emergency declaration as he encouraged the 17-member congressional committee to find another way out of the impasse. “I’m for whatever works, which means avoiding a shutdown and avoiding the president feeling he should declare a national emergency,” McConnell said during his weekly news conference in the Capitol.

McConnell’s top deputy, Sen. John Thune, R-S.D., told Republican senators at a private lunch that same day that if they had issues with the president declaring a national emergency they should raise them with the White House, according to one of the Republicans and another person with knowledge of Thune’s comments, who spoke on the condition of anonymity to describe them.

The prospect of Trump using a national emergency declaration to build his wall has divided Republicans, with a number of them expressing concerns about the precedent that such a move would set.

Sen. John Cornyn, R-Texas, a top McConnell confidant, said this week that he is opposed to a national emergency declaration in part because of what it might embolden a future Democratic president to do.

“We’ve certainly tried to communicate that to him,” said Cornyn, referring to Trump. “And so, he understands our concerns as we’ve expressed them. But I don’t know if he shares those same concerns.”

Other Republican senators took a different view.

“President Trump proposed logical solutions,” said Sen. Rick Scott, R-Fla. “If the Democrats won’t negotiate with him because their judgment is clouded by their pure hatred of him, then the president needs to move forward.”

Lawmakers of both parties expect that a national emergency declaration would be immediately challenged in court, and would end up languishing in legal proceedings without producing quick action on the border wall Trump long promised Mexico would pay for.

And a growing concern for Republicans – which McConnell voiced to Trump at the White House – is that they would be forced to vote on a disapproval resolution aimed at overturning the declaration, and that the resolution would pass.

That would take place under provisions of the National Emergencies Act, which provides that a presidential declaration can be terminated if lawmakers pass a joint resolution to do so. House Democrats would be likely to move swiftly to approve such a resolution, and the law provides that it would come to the Senate floor, where it would require only a majority vote to pass.

RARE RESOLUTION

At least a half-dozen Republican senators are fiercely opposed to the idea of an emergency declaration, generating enough opposition that a disapproval resolution could pass the Senate with the support of the 47 Democrats and a handful of Republican senators – the scenario McConnell warned Trump about. Republicans expect that Trump would veto the resolution, and that the House and Senate would not be likely to muster the supermajority vote needed to override his veto.

A disapproval resolution on a presidential emergency declaration is rare, so exactly how the process would play out is uncertain. But it could expose new divisions within the party on Trump’s signature issue of a border wall, creating a portrait of disunity that most Republicans would like to avoid.

An emergency declaration would also risk further political damage to Trump, whose disapproval rating rose significantly over the 35-day partial government shutdown as more Americans faulted Trump than Democrats for the standoff.

While Trump stood on weak political ground demanding a wall which most Americans continue to oppose, an even larger majority opposes Trump declaring a national emergency to build it.

A Washington Post-ABC News poll during the shutdown found 66 percent of Americans opposed Trump using emergency powers to build the wall without approval from Congress, 12 percentage points higher than opposition to the wall in general. Seven in 10 independents and about 9 in 10 Democrats opposed Trump declaring an emergency to build a wall.

Trump is pitted between the political middle and his own base, which has embraced his demand for a border wall. While Republican support for using emergency powers to build a wall was 20 points lower than for the wall overall, 67 percent of Republicans favored Trump taking emergency action, including a majority who supported this “strongly.”

Facing a deadline for a compromise, House Republicans on the conference committee plan to travel to the border Sunday and Monday.

The Oval Office discussion over a national emergency declaration illustrated the dynamic that has developed between Trump and McConnell. The two speak frequently, people familiar with their conversations said, with McConnell often providing Trump with blunt details about what a certain decision or course of action could mean on Capitol Hill.

But even as they have kept in touch privately, in public their strategies have diverged. Although McConnell has warned about the perils of another shutdown or a national emergency, Trump has dangled both as possibilities.

“I think some of their goals are aligned but the methods to get there might be different,” said Sen. Richard Shelby, R-Ala. Asked how they differ, Shelby replied, “You have to ask them but I think it’s pretty obvious.”