WASHINGTON — Hours after President Trump signed an executive order Wednesday to temporarily halt the separation of migrant children from their parents at the border, a compromise immigration bill that the House is slated to consider Thursday appeared in jeopardy amid fresh conservative criticism.

Rep. Mark Meadows, R-N.C., the chairman of the conservative Freedom Caucus which was involved in negotiations that led to the compromise bill, was seen arguing with Speaker Paul Ryan, R-Wis., during the final vote series on Wednesday on the House floor ahead of a planned floor vote Thursday.

“At this particular point, the compromise bill is not ready for primetime," Meadows told reporters. "There are things that were supposed to be in the compromise bill that are not in the compromise bill that we had all agreed to.”

Meadows added that there are “a number of issues with the drafting of the compromise bill,” but declined to elaborate on what he believes is missing from the bill. Asked if Ryan said that he’d be willing the change the bill’s language, Meadows said, “No, he did not.”

The Freedom Caucus hasn't taken a formal position on the bill, said Meadows, but if the group votes as a bloc, that could cause the bill to fail, assuming all House Democrats opposed the measure.

House GOP Chief Deputy Whip Patrick McHenry (R-N.C.) told reporters leaving the leadership meeting that no changes had been made” to the voting schedule, and that member concerns could be addressed in the Rules Committee ahead of the floor votes Thursday. He blamed the new problems on staff miscommunication.

A Meadows spokesperson later tweeted that the congressman had since spoken with Ryan, and was "working to resolve a communication issue on the compromise immigration bill.”

Speaker Paul Ryan had resisted pressure to address the widely unpopular family separation policy in standalone legislation, saying the issue should be addressed as part of the broader compromise immigration measure. President Trump's decision to sign an executive order temporarily dealing with the policy Wednesday afternoon eliminated much of the urgency surrounding the most unifying element of the bill.

Trump also met in the afternoon with roughly two dozen House Republicans at the White House to discuss the two measures. Trump, who was under pressure from members of his party to address the "zero tolerance" policy his administration implemented in April, was expected to personally urge those lawmakers to support the compromise immigration bill up for a vote Thursday, two GOP leadership sources said. House Majority Whip Steve Scalise, R-La., gave the White House a list of people the president personally needed to lobby in order for the compromise legislation to pass.

Back on Capitol Hill, Attorney General Jeff Sessions met with Senate Republicans to discuss the immigration issue Wednesday, while Homeland Security Secretary Kirstjen Nielsen fielded questions from some House Republicans behind closed doors.

Even after Trump signed the executive order, GOP lawmakers said there is still a need to address immigration through legislation.

"I think the president is trying to address the issue on the border in a compassionate way and trying to do what he can from an executive standpoint. But it has to be addressed legislatively," Meadows said.

Rep. Bob Goodlatte, R-Va., who authored the more conservative of the two GOP immigration bills the House is set to vote on Thursday, said an immigration bill was "still very, very necessary" in light of the temporary nature of Trump's executive order.

"He's gonna have an executive order that's going to allow children to be with their families which has always been possible, but only for a very short period of time because of court cases," Goodlatte said.

And Rep. Jeff Denham, R-Calif., a moderate Republican and sponsor of the compromise immigration bill, agreed that the executive order cannot permanently fix the problem.

“The president’s executive order does not alleviate Congress of its responsibility to legislate,” he said in a statement. “Separation of families is absolutely intolerable, and I urge my colleagues to join me in taking immediate action.”

Technically, the president’s executive order won't stop the detention of children or Trump's "zero tolerance" policy of charging people with a misdemeanor for entering the country illegally, but will allow them to be held with their parents pending "any criminal improper entry or immigration proceedings involving their members."

A White House official told NBC News earlier Wednesday that while Trump prefers that Congress pass one of two immigration bills that the House is set to vote on Thursday, the president would support a narrow legislative fix specifically aimed at halting his administration's policy of family separation should those two measures fail.

Meanwhile, Senate Majority Leader Mitch McConnell, R-Ky., said Tuesday that he would back a narrow bill targeting the policy.

Speaker Paul Ryan, R-Wis., said at a House GOP leadership press conference Wednesday that the House still intends to vote Thursday on a more conservative bill authored by Rep. Bob Goodlatte, R-Va., chairman of the House Judiciary Committee, and a compromise immigration bill.

“Tomorrow, the House will vote on legislation to keep families together,” Ryan said. “Under this [compromise] bill, when people are being prosecuted for illegally crossing the border, families will remain together under DHS custody throughout the length of their legal proceedings.”

Ryan, however, wasn’t exactly confident that the compromise bill would pass.

“I hope that we will be able to pass this tomorrow,” he said.

Asked if House GOP leaders would entertain a narrow, emergency bill, Ryan said that he’s only focused on passing the compromise bill first.

“When other situations arise, we’ll cross those bridges when we get to it,” he said.

Three House GOP leadership sources told NBC News Wednesday that the effort to try and garner enough votes to pass the compromise immigration bill through the House is continuing Wednesday, but that the president needs to lean in more and state point blank that he wants the compromise bill on his desk.

Members were skeptical of the compromise bill's chances.

“I’m not yet certain it’ll pass,” said Rep. Tom Cole, R-Okla.

“I think getting this compromise bill to the finish line is going to be a lot more challenging than I would have anticipated," said Rep. Ryan Costello, R-Pa., who’s retiring from Congress at the end of this year. "The conservatives aren’t going along with it. [For them,] it’s Goodlatte or nothing.”

Costello criticized the idea of passing a narrow fix for family separation because he said that the president could end the policy unilaterally.

“This notion that somehow we can pass a standalone bill for family separation, to me, what’s the point of that when the president can just do it on his own,” Costello said. “He can stop it a heck of a lot quicker than it’ll take for us to go through the legislative process...there’s no point to pass a stand-alone.”

One big issue for GOP members is figuring out which of the broader immigration bills up for a Thursday vote the president would prefer they support, and whether he backs the compromise bill — a question his Hill visit Tuesday appears to have left unresolved.

Trump huddled behind closed doors with House Republicans Tuesday evening on Capitol Hill and said that he is “1000 percent” behind them as they prepare to vote on the two pieces of legislation, but some lawmakers said that he didn’t explicitly speak in favor of the compromise bill.