South Carolina Republican Sen. Lindsey Graham threatened on Wednesday to oppose Kentucky Sen. Mitch McConnell’s re-election to leadership if the GOP minority leader can’t work with former President Donald Trump.

“I like Sen. McConnell. He worked well with President Trump to get a bunch of judges including three Supreme Court justices on the bench. They got the tax cuts passed working together,” Graham said on Fox News. “But here’s the question: Can Sen. McConnell effectively work with the leader of the Republican Party Donald Trump? I’m not going to vote for anybody that can’t have a working relationship with President Trump.”

Graham’s comments follow months of McConnell endorsing a purge of the former president and his supporters by legitimizing the Democrats’ weaponized House Select Committee on Jan. 6.