Chelsy, 32, who was Prince Harry's first serious girlfriend, has been spotted passionately kissing TV producer James Marshall, 44, who was once married to Elettra Wiedemann, daughter of Isabella Rossellini and close pal of Meghan, Harry's fiancée.
A source told the Daily Mail: ''It's not clear if Meghan introduced Chelsy to James, but this keeps everyone happy.''
Meanwhile, Harry has invited Chelsy and his other former longterm love Cressida Bonas to attend his wedding to Meghan, 36, at Windsor Castle on May 19.
A source said previously: ''Harry has stayed good friends with Chelsy and Cressida, so they will be there. He made sure there were no hard feelings when they split up. I don't think Meghan will mind.''
Harry dated Chelsy for seven years, while his relationship with Cressida, 29, ended after two years.
However, Meghan's former husband Trevor Engelson has not been invited as the film producer is currently working on a TV show about a divorcee who marries into the Royal Family.
Meanwhile, Harry previously revealed he knew Meghan was 'the one' the ''very first time'' they met.
The 33-year-old royal - who was also romantically linked to singers Mollie King and Ellie Goulding, actress Jenna Coleman and presenter Caroline Flack - proposed to the 'Suits' actress in November after 16 months together and he revealed they shared an instant connection.
Speaking to reporters at a photocall in the grounds of London's Kensington Palace, Harry was asked when he knew Meghan was the one and said: ''From the very first time we met.''
The prince said he was ''thrilled'' and ''over the moon'' with the news, while Meghan gushed she was ''so happy'' as she showed off her stunning three-stone diamond ring and held onto her new fiancé's arm.
The couple posed for pictures just a few hours after their engagement was formally announced by Harry's father, Prince Charles.
An official statement read: ''His Royal Highness, the Prince of Wales, is delighted to announce the engagement of Prince Harry to Ms. Meghan Markle.
''The wedding will take place in Spring 2018. Further details about the wedding day will be announced in due course.
''His Royal Highness and Ms. Markle became engaged in London earlier this month.
''Prince Harry has informed The Queen and other close members of The Royal Family.
''Prince Harry has also sought and received the blessing of Ms. Markle's parents.
''The couple will live in Nottingham Cottage at Kensington Palace.''
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