A Virginia state lawmaker has issued an ultimatum to Lt. Gov. Justin Fairfax, demanding that he step down immediately or face impeachment.

“On Monday, I will be introducing articles of impeachment for Lt. Governor Justin Fairfax if he has not resigned before then,” threatened Patrick Hope, a Democratic member of the Virginia House of Delegates, in a tweet on Friday night.

Fairfax is facing at least two accusations of sexual assault — with a second alleged victim coming forward earlier in the day. The 39-year-old Democrat has denied the allegations, calling them “unsubstantiated” and “demonstrably false.”

Lawmakers on both sides of the aisle were calling on him to resign Friday.

“The allegations against Justin Fairfax are serious and credible,” tweeted former Virginia Gov. Terry McAuliffe. “It is clear to me that he can no longer effectively serve the people of Virginia as Lieutenant Governor. I call for his immediate resignation.”

Fairfax has denied both of the sexual assault accusations, the first of which came earlier in the week. He has called for a “full investigation” into the claims, saying it “will confirm my account because I am telling the truth.”

“I have never forced myself on anyone ever,” Fairfax said in a statement Friday. “I have passed two full field background checks by the FBI and run for office in two highly contested elections with nothing like this being raised before. It is obvious that a vicious and coordinated smear campaign is being orchestrated against me.”