"It wasn't like he and I had bantered back and forth or flirted. I said (to Tambor), 'It was very nice to work with you' and he grabbed me out of nowhere and kissed me on the lips," she claimed.
The make-up artist made the claims in an interview with the website Refinery29.
She added: "And I was just shocked. I didn't even know how to react, because how do you react when you're not expecting anything like that?
"So I didn't know if I was embarrassed or shocked or mortified or stunned. It was a whole bunch of emotions."
Tambor last night said he had no recollection of the incident, but nevertheless offered the woman an apology.
"If it did, it wasn't meant as anything more than an enthusiastic farewell and gratitude for a job well done at the end of a shoot," he said.
"However, I am deeply sorry for any discomfort or offence I may have inadvertently caused her."