President Trump’s uneasy alliance with his Republican majorities in Congress is beginning to teeter.

Top lawmakers and party aides accused the White House of blindsiding them with an executive order on immigration that sowed chaos at major U.S. airports, contradicting administration officials who claimed that Capitol Hill had taken a leading role in writing the policy. Senior aides to the chairmen of the House Homeland Security, Judiciary, and Foreign Affairs committees all said the White House failed to consult them on the immigration directive, which led to lawsuits and widespread protests across the country over the weekend. More Republican lawmakers issued statements critical of Trump’s action on Sunday evening and Monday, even as many said they supported a temporary halt to the refugee program and restrictions on travel from Muslim countries.

“It would have been smarter to coordinate with us,” Representative Dave Brat of Virginia, a Trump ally, said in a phone interview on Monday. “They could have done a better job announcing how the complexities were going to work in advance.”

Republicans were particularly angry that the Trump administration did not initially exempt green-card holders, or those who had served as military or diplomatic interpreters from the ban. “In the future, such policy changes should be better coordinated with the agencies implementing them and with Congress to ensure we get it right—and don’t undermine our nation’s credibility while trying to restore it,” Representative Michael McCaul of Texas, the chairman of the Homeland Security Committee, said in a statement.

A senior administration official told reporters in a background briefing on Sunday night that “Republicans on Capitol Hill wrote” the policy—a statement that Sean Spicer, the White House press secretary, defended on Monday. But multiple top Republican aides said the assertion was false.

“Ha! That’s my formal response,” said one senior GOP aide. “There was precisely zero coordination with us on the drafting of this executive order.” The aide said that one or two “rogue staffers” with the House Judiciary Committee had worked informally with the White House on the order, but that the administration never formally involved the relevant congressional leaders. Separately, an aide with the Judiciary Committee said that the panel’s chairman, Representative Bob Goodlatte of Virginia, was “not consulted by the administration”—a sign that the staffers working under him had helped the White House without Goodlatte’s knowledge. Politico reported Monday night that the Judiciary Committee staffers signed nondisclosure agreements.

The aides insisted on anonymity to avoid provoking a further fight with the new president, but they spoke with more candor than the more diplomatic statements that GOP members of Congress have released in recent days. Officials said John Kelly, the secretary of homeland security, will meet with a bipartisan group of lawmakers Tuesday in the Capitol to discuss the the executive order.

Trump’s executive order has plenty of support from conservative immigration hawks on Capitol Hill, including from those, like Brat, who thought the administration stumbled in rolling it out. “I think there’s a need for some of these moves before something happens that’s really bad,” Brat told me, referring to the fear that a terrorist might infiltrate the refugee program or otherwise slip into the United States without being detected. Echoing Trump, he faulted both the media and Democrats for overreacting to the order and exaggerating the havoc it wrought at airports.

Many other Republicans, however, argued that the order was overly broad and poorly vetted, leaving them unable to properly defend a policy they would otherwise support on narrower grounds.

“While we certainly need to enhance our current vetting process and significantly reform our immigration policies to make sure terrorists are not exploiting our nation’s proud tradition of freedom and acceptance, the president's policy entirely misses the mark,” Representative Brian Fitzpatrick of Pennsylvania, a freshman Republican, said on Monday.

One senior GOP aide said that some of the confusion about congressional involvement in the executive order resulted from comments that former New York Mayor Rudolph Giuliani made Saturday night on Fox News, in which he said the policy began when Trump asked him to form “a commission” to draft a “Muslim ban” in a legal way. That group included McCaul, Representative Peter King of New York, and former Attorney General Michael Mukasey, according to Giuliani. The congressional aide familiar with the talks said all the group did was write a memo for Trump that explicitly advised him not to pursue a blanket ban on Muslims entering the U.S., as he had promised on the campaign trail.

“The memo made a forceful case against some kind of categorical ban on Muslims and made the case that the then-candidate needed to narrowly target the political ideology driving Islamist terrorism,” the aide said. “It then more broadly made the case that Muslims who embrace American values and our principles are actually an asset to U.S. national security and to our national fabric.”

“Our hope,” the aide continued, “was to get him to stop saying Muslim ban and to stop pushing those policies and to focus on real counter-terrorism policies to keep the bad guys out of the United States.”

Was the executive order consistent with the memo’s advice? “Mostly no,” the aide said. The memo did not recommend banning entry from any of the seven majority-Muslim countries singled out in the executive order.

The GOP aide also rejected Trump’s argument, made in a tweet on Monday, that if he had announced the ban with more notice, “the ‘bad’ would rush into our country during that week.” It takes up to two years for foreign travelers to enter the U.S. through the refugee program the order suspended, and at least several weeks to get visas from the countries affected by the wider travel ban. “We think that was bad policy, and it had a bad outcome. It's not a logical justification,” the aide said. “There was no risk of terrorists flooding into the country if they had shared this in advance.”

The number of Republican lawmakers criticizing the executive order or its implementation grew to more than two dozen on Monday, according to a Washington Post tally, and they included several powerful members of the Senate: John McCain, Lindsey Graham, Lamar Alexander, Susan Collins, and Bob Corker. Trump retained stronger support among the party leadership, but the complaints from senior lawmakers and aides were an indication that the warm feelings of unity with the administration generated by the GOP’s policy retreat in Philadelphia last week had chilled considerably. And they cast doubt on the claims by party leaders that the White House was working “hand-in-glove” with Republicans in Congress on the agenda.

It’s also not clear that Trump places a high priority on a close relationship with Congress in the first place. The president needs Republicans to stick together to pass his agenda, particularly in the Senate. But he has not hesitated to attack members of the party who criticize him, most recently McCain and Graham on Sunday.

Despite the criticism of his immigration move, there was no indication of a widespread Republican revolt against Trump fewer than 10 days into in presidency. GOP lawmakers quickly turned aside Democratic attempts in the House and Senate for a vote overturning the executive order Monday night, and Republicans aides said there were no immediate plans for a legislative response.