Republican Rep. Justin Amash leaves conservative House Freedom Caucus after calling for Trump's impeachment

Observers believe Amash has grown frustrated with the caucus leadership.

Rep. Justin Amash, the first Republican to call for President Donald Trump's impeachment following the release of the Mueller report, has left the conservative House Freedom Caucus and its board, a source close to Amash confirmed to ABC News on Tuesday.

"I have the highest regard for them and they're my close friends," Amash told CNN on Monday. "I didn't want to be a further distraction for the group."

The caucus was officially founded by conservatives in 2015 at the House Republican retreat in Hershey, Pennsylvania, and now includes more than 30 members. It's chaired by Rep. Mark Meadows, a third-term Republican from North Carolina. Beyond Meadows and Rep. Jim Jordan, R-Ohio, Reps. Justin Amash, R-Mich., Raul Labrador, R-Idaho, and Ron DeSantis, R-Fla., were all founding members and still serve in the House of Representatives.

Following Amash's remarks about Trump's impeachment, the House Freedom Caucus came out strongly against him.

“We had a good discussion and every single member, I think now based on who was there and our board meeting was probably over 30 members, every single member disagrees and strongly with the position Justin took over the week, and we're focused on the now,” Jordan said to reporters.

The Michigan lawmaker opposed Trump’s primary campaign and in the past couple years close observers believe he has grown frustrated with the caucus’s leadership, including Trump loyalist Meadows and Jordan.

While Amash has not signed on to any existing impeachment resolutions proposed by Democrats, in a town hall in Grand Rapids he said it is appropriate for Speaker Nancy Pelosi to proceed with impeachment inquiries and hearings. Ultimately, he says, the ball is in Pelosi's court regarding how to go forward.

"I think it's really important that we do our job as a Congress, that we do not allow misconduct to go undeterred, that we not just say someone can violate the public trust and that there are no consequences to it," Amash said.