House GOP leadership is urging President-elect Donald Trump to refrain from tapping any more Republican members for his administration — at least for now.

Republicans have not officially clinched the House majority yet, though they’re expected to do so with a narrow margin, likely just a handful of seats more than Democrats. Meanwhile, Trump has already named two House Republicans, Conference Chair Elise Stefanik (R-N.Y.) and Rep. Mike Waltz (R-Fla.), to positions within the administration.

Speaker Mike Johnson told reporters on Tuesday that he and Trump have discussed the math crunch he faces in the Capitol.

“President Trump and I have talked about this multiple times a day for the last several days. … I don’t expect that we will have more members leaving,” Johnson said, adding that Trump “fully understands and appreciates the math here.”

GOP leadership will likely already have a tough time navigating a slim majority, both during major policy fights and the speaker election. And unlike the Senate, House members can’t get quickly reappointed replacements; leaders will have to wait to have those spots filled via special elections, which typically take months.

Majority Leader Steve Scalise added that “hopefully” Trump will pick “no more for a little while,” or at least until there are special elections to fill Waltz and Stefanik’s seat. Neither member has said yet when they intend to resign from their House seats. Stefanik’s position as UN ambassador will require Senate confirmation, which can take weeks, but Waltz can assume the national security adviser position as soon as Trump is inaugurated.

Other House Republicans have been floated for potential spots within the administration, including Rep. Mike Rogers (R-Ala.) and several other members of the Florida delegation. But members are clearly getting nervous about Trump taking more from their thin ranks.

“He can’t pick many more. Our majority is way too thin,” said a House Republican, granted anonymity to speak frankly.