Speaker of the House Paul Ryan mourned Sen. Jeff Flake’s (R-AZ) decision not to seek re-election, describing his retirement as a loss for “the greater cause of conservatism.”

“I’m saddened Congress is losing my friend Jeff Flake. Throughout his career in public service, Jeff has been a champion of constitutional, limited government and a trailblazer for fiscal restraint,” Ryan said in a statement.

“He as much as anyone helped to end a corrosive earmarking process that enabled runaway spending. Jeff’s retirement is a loss to the Senate and the greater cause of conservatism. I wish him well as he continues to advocate for our principles outside of government.”

Ryan and Flake were natural allies in Congress, both championing the causes of unrestrained free trade and presiding over unprecedented levels of illegal immigration, as well as critics of the Trump agenda.

Flake said in announcing his retirement:

It is clear at this moment that a traditional conservative, who believes in limited government and free markets, devoted to free trade, pro-immigration, has a narrower and narrower path to nomination in the Republican party. I rise today with no small measure of regret. Regret because of the state of our disunion, regret because of the disrepair and destructiveness of our politics.”

Flake was part of the “Gang of Eight” that proposed the 2013 immigration bill seeking to provide amnesty to millions of illegal immigrants, alongside the likes of Sens. Marco Rubio, John McCain, and Lindsey Graham.

“It’s very hard for me to add to the eloquence of my dear friend from Arizona,” McCain said after the decision was announced. “But I do want to say that it has been one of the great honors of my life to serve with a man of integrity, honor, decency, and commitment to not only Arizona but to the United States of America.”

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