(CNN) - House Speaker Paul Ryan called allegations leveled against Alabama Republican Senate candidate Roy Moore about pursuing relationships with teenage girls and committing sexual assault "credible" and that he should step aside.
"He should step aside," Ryan told CNN Tuesday morning. "Number one, these allegations are credible. Number two, if he cares about the values that he claims to care about, then he should step aside."
Ryan becomes the latest high-profile Republican voice to call on Moore to step aside, following more than two dozen Republican senators, including some of whom have suggested voting to expel Moore from the Senate should he win the December 12 special election.
The flood of condemnation and calls to step down replaced what had been days of heavily caveated statements defined by senators calling for Moore to step aside "if" the allegations "were true." Starting Monday with Ryan's counterpart, Senate Majority Leader Mitch McConnell, the tone from national Republicans shifted dramatically.
An Alabama woman alleged Monday that Moore sexually assaulted her when she was a teenager. Moore called the accusation "absolutely false" in a statement in Gallant, Alabama, later Monday, denying that he knew the woman.
The accusations came after The Washington Post published a report last week based on interviews with more than 30 people, saying Moore pursued relationships with teenagers while he was in his 30s. One woman said she was 14 years old when Moore initiated sexual contact with her. Moore also denied those allegations and has threatened to sue the Post.
For now, GOP leaders are stuck in an increasingly difficult position. Moore has repeatedly said he has no intention of stepping down and views the stories themselves -- and the GOP senators that have condemned him in its wake -- are nothing but political attacks. Senate Republicans made clear they are weighing several options on how to go forward, ranging from pushing for a write-in campaign to trying to vote Moore out of the Senate should he win.
One Republican senator, Jeff Flake, the Arizonan who announced last month he would retire at the end of his term, became the first to present another choice Monday night: support Moore's opponent.
"If the choice is between Roy Moore and a Democrat, a Democrat no doubt," Flake told reporters.