Updated at 8:15 p.m. ET

House Speaker Paul Ryan, R-Wis., says the rash of sexual harassment and sexual assault allegations coming to light could end up being a "watershed moment" in changing the culture — including on Capitol Hill — that has covered them up far too long.

"We are having a watershed moment in this country. I think this is a defining moment in this country. And I think it needs to be a defining moment in this country," Ryan told Morning Edition's Steve Inskeep in an interview on Capitol Hill on Thursday.

"I think we're all horrified at these stories we've been seeing unfold in the last few weeks. I think we're all realizing that sexual harassment in America is absolutely pervasive and it's got to go and we need to end it," Ryan continued. "And nowhere more is this important to set a standard and an example than elected officials. We should be held to a high standard."

Politicians in both parties have been accused of sexual misconduct in recent weeks. On Thursday, Ryan called for Rep. John Conyers, D-Mich., to resign after a former aide made public her allegations of sexual harassment against the veteran lawmaker. House Minority Leader Nancy Pelosi, D-Calif., also called on Conyers to step down. The Michigan Democrat has been hospitalized for stress.

Another accuser also came forward on Thursday against Sen. Al Franken, D-Minn., alleging that he groped her during a 2003 photo opportunity, bringing his total accusers to five women who say the senator groped or forcibly kissed them in recent weeks. The Senate Ethics Committee confirms it has launched an initial inquiry into the allegations against Franken.

Meanwhile, Republicans are continuing to grapple with Alabama GOP Senate nominee Roy Moore, who has been accused by multiple women of sexual assault when they were teens and he was in his 30s. Several women say he pursued them romantically, and one woman said he had sexually assaulted her when she was 14.

Moore has denied the allegations, but Ryan, Senate Majority Leader Mitch McConnell, R-Ky., and other top Republicans have called on him to step aside. Moore has resisted. The White House has said that if the allegations are true, Moore should step aside, but President Trump has not gone as far as others in pushing Moore to leave the race. Trump in recent days has pressed the importance of not losing the seat to a Democrat.

Trump himself was accused of sexual assault by several women during the 2016 campaign, allegations he continues to deny. And in a 2005 Access Hollywood tape that surfaced just ahead of the election Trump bragged about groping and forcibly kissing women. According to reports, Trump has now begun to privately assert that tape was a fake, despite acknowledging its veracity last year.

Inskeep asked Ryan about the differences between the allegations against Moore — which the House speaker reiterated he believed were "very, very credible" — and the accusations against Trump.

The speaker said he was "focused on Congress" because that's where Moore wants to go. "My job here as speaker of the House is to help make sure that Congress is an institution that we're proud of and that's what I'm focused on," he said.

Asked again about the differences, Ryan said, "I haven't spent my time reviewing the difference in these two cases."

Ryan admitted, "It's no secret that [Trump] and I have had our differences of opinions," but he underscored they still align on policy issues and goals.

"What I see is a president who is fighting for the things that I'm fighting for. I see a president who's fighting for an agenda that will make a positive difference in people's lives," Ryan said. "Is this president unconventional? No two ways about it. He's very unconventional. But if we make good by the American people by actually improving their lives and fixing problems and finding solutions that are bothering them? That's a good thing."

All these recent political allegations are in addition to women coming forward with stories of sexual assault against high-profile Hollywood moguls such as Harvey Weinstein and journalists like NBC's Matt Lauer, CBS' Charlie Rose and top NPR executives as well.

Ryan told NPR that, as a father, the issue is a personal one for him as he has watched the swirl of scandal over the past few weeks.

"I want my daughter to grow up in a country — she's 15 years old — where she is empowered and respected. Wherever she goes, wherever she works, and whatever she does. And I think nowhere should that be more obvious and apparent than working here on Capitol Hill," Ryan said.

"So I think here in Congress we should set ourselves to standards that we expect of other people," the House speaker added. "We should set high standards for ourselves, so that we can be role models and set examples, and clearly people have been falling short of that, and I think we always have to endeavor to do a better job on that."

Congress has recently passed legislation to adopt mandatory training on harassment and discrimination for lawmakers and Capitol Hill employees. In a news conference on Thursday, Ryan applauded the legislation but also said, "This is an important step, but it's one step."

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