WASHINGTON (AP) — A former aide to Republican Rep. Trent Franks has told The Associated Press the congressman repeatedly pressed her to carry his child, at one point offering her $5 million to act as a surrogate mother.

The eight-term lawmaker abruptly resigned Friday, bowing to an ultimatum from House Speaker Paul Ryan, R-Wis. Ryan told Franks that he would refer the allegations to the Ethics Committee and urged him to step aside.

The former staffer said the congressman at least four times asked if she'd be willing to act as a surrogate in exchange for money. Franks, in his statement announcing his resignation, said he and his wife, who have struggled with infertility, have twins who were carried through surrogacy.

The former aide said the conversations took place in private, sometimes in the congressman's car, and that she repeatedly told him she wasn't interested. She said she never filed a formal complaint because until recently she didn't know where to go, but that his behavior had made her feel uncomfortable.

The Associated Press verified the identity of the staffer and confirmed that she worked in Franks' office. She asked that her name be withheld out of concern for her privacy,.

"During my time there, I was asked a few times to look over a 'contract' to carry his child, and if I would conceive his child, I would be given $5 million," she said, adding that she refused to look over the contract and has never seen a copy.

The woman said the requests shocked her, and made her feel afraid that if she didn't agree, she would face professional consequences. She said she spoke to another aide in the office, who had also been approached about surrogacy.

The aide cited the surrogacy requests as "a main reason" for leaving the office, adding that she felt retaliated against after turning down the congressman, ignored by Franks and not given many assignments.

A spokesman for Franks would not comment on whether the congressman offered aides money in exchange to act as surrogates.

Franks, a staunch conservative, said in his statement Thursday that he never physically intimidated, coerced or attempted to have sexual contact with any member of his congressional staff.

Franks, 60, said he had become familiar with the surrogacy process in recent years and "became insensitive as to how the discussion of such an intensely personal topic might affect others."

He said he regrets that his "discussion of this option and process in the workplace" with two female staffers made them feel uncomfortable.

Ryan on Thursday said in a statement that he was briefed on the allegations last week, and found them to be "serious and requiring action."

Ryan said that he presented Franks with the allegations, "which he did not deny," and filed them with the House Committee on Ethics.

A senior congressional official said Ryan's general counsel was contacted about two weeks ago by someone with information about "troubling behavior" by Franks involving a former staffer. Ryan's lawyer interviewed two women with similar complaints and verified them through a third party. The official spoke on condition of anonymity because the official was not authorized to discuss the deliberations.

Andrea Lafferty, President of Traditional Values Coalition, said she is the one who reported Franks' conduct to the speaker's office. Lafferty told AP that the former aide came to her about a year ago and told her about the surrogacy requests. Lafferty said she contacted Ryan's office last month, after the staffer agreed to discuss the incident with leadership.

"I was approached last year about the situation, she came to me wanting some advice about how to handle this. She came to me shaking and sobbing, and she shared a story that I think is horrific, a powerful man hiring young women, procuring staff, to potentially surrogate children for him," Lafferty said. "I accompanied (the former aide) to the meeting in the speaker's office where she said Congressman Trent Franks offered her $5 million if she conceived him a child."

Franks' net worth of nearly $33 million makes him one of the wealthier members of Congress. While surrogacy regulations and costs vary from state to state, services typically run in the range of the low hundreds of thousands of dollars. The former aide said she never received details about payment or where the process would occur.

Franks is one of three lawmakers to step aside in a week as sexual misconduct allegations rocked the Capitol.

He said in a statement Friday: "Last night, my wife was admitted to the hospital in Washington, D.C., due to an ongoing ailment. After discussing options with my family, we came to the conclusion that the best thing for our family now would be for me to tender my previous resignation effective today, December 8th, 2017."

On Thursday, liberal Sen. Al Franken, D-Minn., announced his resignation after facing allegations of sexual harassment by at least eight women. Franken said some of those accusations were false and that he remembered others differently than his accusers did. He said he'd depart in a few weeks.

On Tuesday, Rep. John Conyers, D-Mich., resigned effective immediately. He faced accusations from women of improper sexual behavior that he's contesting.

Franks, an abortion opponent, drew a sharp response from Democrats during a 2013 House committee debate when he said, "The incidence of rape resulting in pregnancy are very low." He sought to clarify the comment, saying later-term abortions linked to pregnancies caused by rape are infrequent.

Franks is a strong backer of President Donald Trump, represents a district encompassing suburbs north and west of Phoenix.

Before winning election to Congress, he served in the Arizona Legislature and founded the Arizona Family Research Institute, an organization associated with Dr. James Dobson's "Focus on the Family."