US Senator Al Franken has responded to a woman's allegations that he groped her as she slept and "forcibly" kissed her in a rehearsal for a comedy skit.
Leeann Tweeden said the two incidents happened in December 2006 on a tour to entertain US troops overseas, before Mr Franken entered politics.
The radio host wrote that the former comic "aggressively" kissed her while saying they had to rehearse a scene.
Mr Franken, a former Saturday Night Live writer, apologised for the grope.
But the Minnesota Democrat said he has a different recollection of the kiss.
"I certainly don't remember the rehearsal for the skit in the same way, but I send my sincerest apologies to Leeann," he said.
"As to the photo, it was clearly intended to be funny but wasn't. I shouldn't have done it."
In an article for KABC, a Los Angeles radio station where Ms Tweedon now works, she recalled feeling victimised by Mr Franken during her ninth USO tour of the Middle East.
"When I saw the script, Franken had written a moment when his character comes at me for a 'kiss'," she said.
"I suspected what he was after, but I figured I could turn my head at the last minute, or put my hand over his mouth, to get more laughs from the crowd."
On the day of the performance, she said he was insistent they rehearse the skit.
But when the moment came he "put his hand on the back of my head, mashed his lips against mine and aggressively stuck his tongue in my mouth".
"You knew exactly what you were doing. You forcibly kissed me without my consent, grabbed my breasts while I was sleeping and had someone take a photo of you doing it, knowing I would see it later, and be ashamed," she wrote.
As a senator for liberal-leaning Minnesota, Mr Franken has cultivated an image for himself as a vocal champion of women's issues, from sexual assault to abortion rights and equal pay.
I'm pleased we made steps to curb military sexual assault today, but I hope we can go further to bring justice to those affected. -Al— Al Franken (@alfranken) March 7, 2014
US President Donald Trump did not respond to reporters during a visit on Capitol Hill when asked if Mr Franken should resign.
Ms Tweeden said she was inspired to come forward more than a decade later after California congresswoman Jackie Speier was interviewed on her morning radio programme.
Mrs Speier told about being sexually assaulted as a young congressional aide in Washington.
She also claimed to know two currently serving members of Congress who "have engaged in sexual harassment", though she did not name them.