Updated at 12:32 p.m. ET

House Speaker Paul Ryan announced Wednesday that he will not seek re-election and will retire in January.

"You all know I did not seek this job," Ryan said, addressing reporters. "I took it reluctantly. ... I have no regrets."

Ryan, 48, cited wanting to be around his adolescent children more often.

"My kids aren't getting any younger," Ryan said, "and if I stay, they'll only know me as a weekend dad. That's it right there."

Ryan has three teenage children. He noted that his oldest just turned 16, which was how old Ryan was when his father died.

"I think we have achieved a heck of a lot," Ryan said, noting that Republicans "did big things."

But the GOP-controlled Congress was only able to pass a signature tax cut legislation. That was something Ryan has been focused on since he entered Congress in 1999. On the other hand, Republicans during his tenure were unable to repeal and replace the Affordable Care Act, advance the ball on entitlement reform or cut the deficit. In fact, the deficit has only gone up. After a high-profile failure last year, Ryan described the Affordable Care Act, also known as Obamacare, as "the law of the land."

And Congress is not expected to get much, if anything, else done this year before the midterms.

Republican challenges

Ryan's departure is the highest-profile retirement yet in what has been a record number of Republicans already heading for the exits. Ryan wasn't the only person to announce his retirement on Wednesday: Rep. Dennis Ross, R-Fla., also said he won't run for re-election.

That means a total of 39 GOP members are not running for re-election — 24 are retiring from public office altogether, while 15 are seeking other positions. Democrats, meanwhile, are facing about half of that number with only 18 of their members not running for re-election to the House.

There have been rumors for some time that Ryan could retire. And his tenure has been something of an uneasy one — even before taking the job. Ryan ran for the post after House Speaker John Boehner was ousted, under pressure from conservatives in his conference.

He was thought to have little interest in the job, given his position as chairman of the powerful House Ways and Means Committee. But he was roundly seen as the only person who could get the votes necessary to be elected speaker.

Those tensions didn't entirely go away within his conference, and then along came Donald Trump. Ryan was critical of Trump's demeanor during the 2016 campaign, but he soon swallowed those criticisms when Trump won.

Hoping to push forward on conservative legislation, Ryan worked with the president more than against, but he was still — on a near-daily basis — quizzed by reporters on the latest Trump tweet or sound-off.

Ryan did not mention Trump in his press conference but a source familiar with the speaker's decision insisted that it had nothing to do with Trump.

Trump tweeted out praise for Ryan on Wednesday, calling him a "truly good man." He also touts his "legacy of achievement that nobody can question."

Looking ahead

Ryan has said he fully expects that this will be his last job in elected politics and the source familiar with the speaker's decision would not discuss Ryan's plans or next steps. "He has always believed this [being speaker] is not a long-term thing," said the source.

But getting out of the spotlight now, especially in the Trump era, could help Ryan should he change his mind about running for office again down the road. Ryan, the vice presidential candidate with Mitt Romney in 2012, is, after all, only 48.

Being a congressional leader is usually not helpful to a politician's public image. They often become lightning rods for political partisanship. By getting out now, one theory goes, Ryan could lay low and potentially run for president at a later date.

Ryan's exit also adds another potential target for Democrats looking to take over the House this year. The filing deadline to get on the primary ballot in Wisconsin is June 1. The primary is Aug. 14.

Although Ryan won his last re-election with 65 percent of the vote, he was facing a strong challenge from Democrat Randy Bryce this year, who had already raised more than $4.7 million.

"Paul Ryan decided to quit today rather than face Randy Bryce and the voters," said Bryce's communications director, Lauren Hitt.

Former Democratic House Speaker Nancy Pelosi of California, the current minority leader, called Ryan "an avid advocate for his point of view."

She added, "Despite our differences, I commend his steadfast commitment to our country. During his final months, Democrats are hopeful that he joins us to work constructively to advance better futures for all Americans."

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