Was it a case of two lips that passed in the night? Josh Hartnett and Rihanna are doing their best to put the kibosh on reports that they had a make-out session at a New York hot spot on Oct. 11, two days after appearing together on MTV's "TRL."

"She's fun, she's a nice girl," the wispy-facial-hair-impaired actor, 29, explains to Us Weekly. "We just met on 'TRL.' I don't know her."

According to Hartnett, who has reportedly proved irresistible over the last year or so to the likes of Scarlett Johansson, Penélope Cruz, Sienna Miller and Helena Christensen (she says they're just pals), he's still very much flying solo.

Rihanna also made with the dating disavowals during a radio chat this week with Ryan Seacrest, who came right out and asked whether there's any truth to the saliva-swapping rumors.

"No, not at all," pooh-poohed the "Umbrella" chanteuse. "All of that was a lie. It's very confusing to me how someone can sit and make up an entire story like this."

Says Rihanna, "I met Josh at 'TRL' ... We hung out two nights after ... and we had fun ..."

So much fun she ended up in Hartnett's lap?

"Not on his lap!" balked the teen popster. "Why would I sit on his lap?!"

(It's a question that's probably been asked before, although we're guessing most of the queries come after the fact, amid lots of self-recrimination.)

Rihanna, who was most recently linked to Shia LaBeouf, believes eyewitness accounts of their supposed "kissing and cuddling" at New York's Pink Elephant were part of a plot to score some PR for the club's branded alcohol, which, by the by, she can't legally drink for another couple of years.

"We hung out after at Pink Elephant," she told Seacrest. "They put in the paper that we were drinking P.I.N.K. Vodka. That whole thing was just a promotion for Pink Elephant because of the special vodka they have there. Of course they put we were making out, but none of the above."

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