Sienna Miller and Rhys Ifans's marriage off the cards?

Friends say the couple are going through "their first serious rough patch" and are desperately trying to repair the relationship.

Sienna, 26, has been filming GI Joe in Europe while Rhys, 39, has been working on the Richard Curtis movie Radio Caroline in Southampton.

The couple were reunited last week in Los Angeles, having not seen each other for several weeks, and they spent much of their time discussing their future.

"It has been very strained and things are very sensitive at the moment," discloses a friend. "They are not over, but Sienna has made some tearful long-distance calls to Rhys and has confided to some of the cast on her movie that things aren't great."

Rhys can be quite jealous and he doesn't like Sienna hanging out with other guys, especially Sean who she seems to have a serious crush on," my source adds.

"She also had lunch with Matthew Rhys in LA in March. They used to date and Rhys is very insecure about him. He wasn't happy they'd met up."

"It was a bit cruel," says my source. "It seems Sienna is the one wanting to cool things a bit."

Image WENN