Actors Sienna Miller and Rhys Ifans will soon end their relationship, reports friends as saying.

The couple are said to be at the lowest point of their relationship and Miller, 26, is said to be growing tired of 39-year-old Ifans, to whom she reportedly got engaged in March.

“It’s awful but everyone who knows them can just see it coming a mile off,” a friend of the couple told Grazia magazine. “Rhys seems madly in love with her still, but everyone is speculating Sienna has grown out of the relationship.

“It’s almost painful to see them together because they’ve gone from being the perfect couple to him looking as if he’s struggling to keep her attention. It’s so sad.”

The pair’s troubles are said to stem from their hectic work schedules — Miller has been busy shooting The Edge Of Love with Keira Knightley and G.I. Joe with Channing Tatum, while Ifans has been busy working in the United Kingdom.

“Sienna promised to spend a week with Rhys,” another friend told Closer magazine. “He arranged his filming schedule, but at the last minute she cancelled her trip, saying she had to work. Rhys hit the roof when he called her and found out she was partying in Los Angeles.”

Ifans is also reportedly unhappy that Miller has been spending time with several actors, including Jared Leto and Sean Penn and her ex-boyfriend Matthew Rhys, who stars alongside her in The Edge Of Love.