The return of ABBA-based musical Mamma Mia! with the Here We Go Again sequel is garnering a lot of positive attention but for two of its main stars working together may have been a little bit uncomfortable - because they used to date. Now British heart-throb Dominic Cooper has revealed he was reminded of romance with his real-life ex-girlfriend, Amanda Seyfried, 32, during the filming of the new movie.

Amanda Seyfried and Dominic CooperDominic Cooper and Amanda Seyfried dated for three years after the first film

The pair famously fell in love after shooting the first film in 2008 and sparked a relationship that lasted for three years.

Now Amanda is happily married to Tom Sadoski, 42, and shares a 16-month-old daughter with him. However, working in close proximity with his former flame has clearly stirred up memories for 40-year-old Dominic.

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In an interview with Attitude magazine, the actor said of working with Amanda: "She’s a friend. It was always going to be OK. You just have to be delicate with those situations. She’s married now and has a beautiful child.

"We knew we were going to be working together [again] on a set, going back to a part which was certainly going to remind us of 10 years earlier, but I know her family, I know her mum, who was there a lot.

"It was a pleasant atmosphere. It was really interesting to see how different our lives are after 10 years. It is a long time and it was nice to spend time [with her]."

The sequel's plot follows Sophie - pregnant this time - and her three fathers, played by Colin Firth, Stellan Skarsgard and Pierce Brosnan.

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Meryl Streep returns as Sophie's mother, Donna, and the new movie also features the addition of new cast member Cher.

Of performing with the singing legend, Dominic added: "It was just, I don't know, so many parts of it were so surreal. Seeing her approach the set... she was quite frightened as well in terms of going in to act on a show where the cast all knew each other very well."