President Trump threatened to pull his endorsement of Rep. Lauren Boebert (R-Colo.) on Saturday, as she campaigned with Rep. Thomas Massie (R-Ky.) ahead of a tough reelection fight.

Trump railed against Boebert in a pair of back-to-back posts on Truth Social, calling her “weak-minded” and asking if there was “anyone interested” in challenging her in the GOP primary for Colorado’s 4th congressional district.

“Boebert is campaigning for the Worst ‘Republican’ Congressman in the History of our Country, Thomas Massie, of the Great Commonwealth of Kentucky, and anybody who can be that dumb deserves a good Primary fight!” Trump wrote in one post.

“Even though I long ago endorsed Boebert, if the right person came along, it would be my Honor to withdraw that Endorsement, and endorse a good and proper alternative,” he said.

Boebert opted to run in the 4th District in 2024, hoping to avoid an expensive and crowded House race taking shape in her previous seat. The seat, which covers the easternmost part of the state, is rated solidly Republican by the nonpartisan Cook Political Report.

The filing deadline for Boebert’s seat was in March, and information from the Colorado Secretary of State’s office indicates she is running unopposed in the June 30 GOP primary.

Boebert, a hardline conservative, has historically been one of Trump’s strongest supporters in Congress, but their relationship has experienced some friction in recent months.

She voiced frustration with the president in December after he vetoed legislation aimed at completing a project that would have delivered water to 50,000 people in southeastern Colorado.

She has also aligned herself with Massie, being one of four Republicans to back a discharge petition on Massie and Rep. Ro Khanna’s (D-Calif.) bill that forced the Justice Department to release millions of files related to convicted sex offender Jeffrey Epstein.

“Yes, I saw the President’s post. No I’m not mad or offended,” Boebert wrote on the social platform X on Saturday in response to Trump’s criticism.

“I knew the risks when I agreed to stand by my friend Thomas Massie. I was, and will be, America First, America Always, and MAGA,” she added.

Massie, whom Trump labeled in a separate post as “a disloyal, ungracious, and sanctimonious FOOL,” is staring down a Tuesday election expected to test Republican voters’ appetite for a congressman willing to publicly defy the president.

Boebert and Sen Rand Paul (R-Ky.), another Republican often at odds with Trump, were in Massie’s district to stump for him on Saturday. Trump’s displeasure with that was clear.

“Word is that Rand Paul and Lauren Boebert, two very difficult, and highly unreasonable, Republican Votes, are right now in the Great Commonwealth of Kentucky, which I won by 31 points, parading around like fools for the Worst “Republican” Congressman in the History of our Party!” Trump wrote.

Massie is facing a primary challenge from retired Navy SEAL Ed Gallrein, who Trump described as “loyal, and MAGA all the way.”