The Scottish actor was in the UK promoting his new film 'The Ugly Truth', when he flirted with Kelly at a premiere after-party held at London’s The Dorchester hotel on Tuesday (04.08.09).
As Kelly - who recently moved in with England rugby ace Danny Cipriani - drank £22 Champagne cocktails, Gerard approached her and invited her to join him in the VIP area. The pair laughed and joked before performing an impromptu steamy salsa dance in the hotel lobby.
A source said: "Gerard sexily bent Kelly over backwards, so he was virtually on top of her. Kelly’s female friends also came up behind and groped his butt. They were dancing cheek-to-cheek in front of everyone. He flung her around while she draped her arms around him."
Gerard, 39, then decided to continue partying up in his hotel suite and invited Kelly - who competed in UK TV show 'Strictly Come Dancing' - to join him.
Kelly had booked a taxi to take her home at 1am, but was persuaded to extend her evening.
A source told Britain's Daily Star newspaper: "Kelly sent the taxi away and went back into the hotel. She headed straight for the lifts up to the bedrooms. Ten minutes later, Gerard jumped in a lift with his friends and headed upstairs too. Kelly finally left at 3am with a big grin on her face."
Earlier in the evening, 29-year-old Kelly had claimed guys have stopped approaching her since she began romancing handsome sportsman Danny last September.
She said: "Everyone knows I’m dating Danny and no-one would dare ask me out or try it on with me while I’m with him."
Gerard has recently been romantically linked to Jennifer Aniston and Cameron Diaz.
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