London, March 17 (IANS) Oscar-winning actress Kate Winslet and Sam Mendes's seven-year-old marriage crumbled down due the director's friendship with Rebecca Hall, says report.

The couple announced their split Monday after struggling to work together while filming 'Revolutionary Road'. Imdb.com reports they drifted apart after the movie wrapped and reports suggest Winslet was furious about the amount of time Mendes spent with 'Frost/Nixon' star Hall after he cast her in two of his plays.

'Sam is a huge admirer of Rebecca's work. He can be quite a lovey at times and really worked well with her, which would obviously wind Kate up. There's no suggestion of anything untoward but undoubtedly the friendship didn't help mend the struggling marriage. They are most definitely just friends. To suggest anything else is wide of the mark,' said a source.

Also Winslet's decision to stay in the US to work in TV drama instead of returning to her native Britain with Mendes for his filming commitments caused a deeper rift between the couple.

'Sam raised several questions over whether she should be doing it, insisting she was above a TV script, and it wouldn't progress her career. Not surprisingly, Kate went ballistic,' said the source.