(CNN) - Arizona Republican Rep. Trent Franks announced in a statement Thursday night he will resign from Congress at the end of January, after the House Ethics Committee said it would investigate allegations against him of sexual harassment.
The House Ethics Committee announced earlier Thursday that it will investigate Franks to determine if he engaged in "conduct that constitutes sexual harassment and/or retaliation for opposing sexual harassment."
In his statement, Franks acknowledged he made staffers "uncomfortable" and that he discussed fertility issues and surrogacy with two female staffers, but denied having ever "physically intimidated, coerced, or had, or attempted to have, any sexual contact with any member of my congressional staff."
"But in the midst of this current cultural and media climate, I am deeply convinced I would be unable to complete a fair House Ethics investigation before distorted and sensationalized versions of this story would put me, my family, my staff, and my noble colleagues in the House of Representatives through hyperbolized public excoriation," Franks said in his statement. "Rather than allow a sensationalized trial by media damage those things I love most, this morning I notified House leadership that I will be leaving Congress as of January 31st, 2018."
House Speaker Paul Ryan's office released a statement saying that Ryan was briefed on "credible claims of misconduct" last week and that Franks did not deny the allegations when he was confronted with them. The Wisconsin Republican said he accepted the letter of resignation Thursday.
Franks' resignation would create a vacancy in Arizona at the end of January, which per Arizona law, would mean Republican Gov. Doug Ducey would have to call an election with a primary in late April or early May and a late June date for the general election.
Franks' announcement came hours after Sen. Al Franken, a Minnesota Democrat, announced he would step down in the wake of allegations about inappropriately touching women and two days after Michigan Democratic Rep. John Conyers announced he was resigning as allegations about his past sexual misconduct increased.
Franks, an eight-term congressman, is the first Republican to announce his resignation since the nationwide reckoning over sexual harassment and assault began this fall.
On Thursday evening, a group of conservative House Republicans gathered around Franks on the floor and prayed with him.
Franks, a self-styled "conservative, Reagan Republican," joined Congress in the early 2000s and has hewed conservative on a range of issues in his time there, with a particular focus on anti-abortion issues.
Until his statement on Thursday, Franks appeared to be headed for re-election, and according to the Federal Election Commission, he raised more than $100,000 through the end of September for the 2018 cycle.
Franks' northwest Phoenix suburb is reliably Republican, having gone to Trump and 2012 Republican presidential nominee Mitt Romney, both of whom won the district by more than 20 percentage points, and Franks easily won re-election last year.
"Congress should be held to the highest ethical standard," said National Republican Congressional Committee Chairman Steve Stivers. "Trent Franks did the right thing in stepping aside."
He supported President Donald Trump last year, even in the wake of the "Access Hollywood" tape, by saying Trump's words, while bad, did not compare to Democratic presidential candidate Hillary Clinton's support of abortion rights.
Franks was involved in Trump's efforts to oust Arizona Sen. Jeff Flake before Flake announced his retirement. Franks, state Treasurer Jeff DeWit and former state GOP Chairman Robert Graham huddled privately backstage with Trump before the President's raucous Phoenix rally earlier this year.
Franks sits on the House Judiciary Committee and the House Armed Services Committee.
Franks drew national ire in 2013 when he said, "Incidents of rape resulting in pregnancy are very low" -- a remark he later said was taken out of context.
This story has updated and will continue to update with additional developments.