The wealthy DeVos family said through a spokesman Wednesday it was cutting off financial support for Rep. Justin Amash (R-Mich.), the fifth-term congressman who this week called President Trump’s behavior “impeachable.”

The Michigan-based family, which made its fortune running Amway, decided to stop donating to Amash before his most recent comments about the president, DeVos family spokesman Nick Wasmiller said in a statement.

“Family members have expressed increasing concerns about a lack of representation for their district, the Third Congressional, and I would say an inability to advance efforts connected to important policy matters,” he said.

Throughout Trump’s presidency, Amash has consistently spoken out against him and his policies. On Saturday, Amash shared on Twitter his thoughts about the findings of special counsel Robert S. Mueller III’s Russia investigation, and concluded that Attorney General William P. Barr was being untruthful, that Trump had engaged in impeachable conduct, and that his fellow Republicans were turning a blind eye because of partisanship.

The DeVos spokesman said he was not speaking for Education Secretary Betsy DeVos, who married into the family.

DeVos family members are megadonors to the Republican Party. Amash, who was not at risk of losing his seat, received $16,200 from them in 2018. They also gave $1 million to the Freedom Partners Action Fund, a super PAC aligned with Amash’s ideology. Amash was a founding member of the House Freedom Caucus, though he has fractured from the group over his public critiques of Trump.

The loss of a major donor could sting in 2020, when Amash will face his first primary challenge since 2014. State Rep. James Lower, who supports the president, launched his bid soon after Amash backed impeaching Trump.

Amash, the only congressional Republican to take this stance, has not ruled out running for president in 2020, probably as a third-party candidate on the Libertarian ticket.

The congressman, who has kept a relatively low profile since his tweets about Trump, told CNN Wednesday he had no reaction to the loss of the DeVos family support.

Amash said he’s mostly avoided media interviews this week because he wanted to present his reasoning “in the most clear-cut, sober way possible.”

But he has been speaking to school children visiting the Capitol about it.

“Don’t let people convince you that principles only matter when the outcome is in your favor,” Amash told a group of eighth graders, CNN reported. “Principles matter especially, and really only, when the outcome is not in your favor.”