Boxing chiefs in California have suspended Bulgarian heavyweight Kubrat Pulev's licence after he "forcefully" kissed a female reporter on the lips during an interview.
Footage emerged of Pulev embracing Vegas Sports Daily's Jennifer Ravalo when asked about fighting Tyson Fury.
Pulev, 37, claimed the pair were friends, but Ravalo said she had only met the boxer a day earlier.
Ravalo's lawyer Gloria Allred said his actions were "unwelcome and unlawful".
The heavyweight has been ordered to appear in front of the California State Athletic Commission (CSAC), who said they "take this incident seriously".
Csac added: "Before he will be licensed to fight in California again, boxer Kubrat Pulev must appear in front of the commission and demonstrate that he will conform to this principle of respect."
The incident happened after Pulev defeated Romania's Bogdan Dinu in Costa Mesa, California on Saturday.
In a statement read out at a news conference, Ravalo said that what Pulev did was "disgusting" and left her "humiliated".
Ravalo, who works under the name Jenny SuShe, said: "Mid-interview he grabbed my face and kissed me. I was immediately shocked and embarrassed, and didn't know how to respond.
"Next, I walked to the table to put my items in my backpack. He grabbed both of my buttocks and squeezed with both of his hands. Then he walked away without saying anything to me and laughed.
"It made me feel uncomfortable and frustrated that Kubrat Pulev would treat me in such an unprofessional manner. I did not encourage or consent to Mr Pulev grabbing my face, kissing me, or grabbing my backside.
"I was there at the event covering the boxing match as a professional member of the press. Kissing a woman on her lips without her consent and grabbing her is not acceptable."
She added: "No woman should be treated this way."
In a statement posted on Twitter on Monday, Pulev had said: "Jenny is actually a friend of mine, and after the interview, I was so elated, I gave her a kiss.
"Later that night, she joined me and my other friends at my post-fight celebration.
"On the video, after our kiss, we both laughed about it and thanked each other. There really is nothing more to this."
Ravalo said she was invited to a party after the fight where "there was an opportunity to interview more fighters". She said Pulev "did not join until the very end of the night".
While there, she claims Pulev "acted like nothing happened". She said he later asked her "to remove the kiss from the interview" - a request she denied.
"I did not remove it and instead posted it because I wanted people to see what he had done to me. I wanted him to be accountable," she added.
Ravalo's representative Allred is a leading women's rights lawyer and has represented clients who have filed lawsuits against the likes of Donald Trump and Tiger Woods. She is also the star of a Netflix series in the US, Seeing Allred.
Allred had written to Andy Foster, the California State Athletic Commission executive officer, and said: "Mr Pulev's reprehensible conduct and battery violates California law as well as the rules of the athletic commission.
"We hereby request that the commission conducts an immediate investigation into the serious allegations.
"We request Mr Pulev's boxing licence be suspended."
During the news conference, Allred took part in a question and answer session, where she said: "Even if she were a friend he would still have to ask and he clearly did not. I think this can be considered sexual harassment."
Vegas Sports Daily released a statement on Monday describing Ravalo as the "victim of an unwanted, unexpected and unsolicited forceful kiss".
"We are working around the clock with Jenny SuShe, and Pulev's management team to further investigate the matter and determine appropriate steps/actions following this unfortunate event," it added.
"We want to make it clear that women should feel safe and comfortable to exercise the duties of their job, free of abuse, advances, harassment, etc, in the workplace."
Pulev pulled out of a world title fight with Britain's Anthony Joshua in 2017 with a shoulder injury.
His 28-fight professional career has featured wins over Dereck Chisora and Hughie Fury and his only professional loss was against Wladimir Klitschko in 2014.