Sienna Miller has reportedly dumped Rhys Ifans for being jealous of her ex-boyfriend.

Sienna, 26, is said to have split from the 'Notting Hill' actor over the phone last weekend, citing their long distance relationship as the reason.

Rhys, 39, is believed to have been upset over the amount of time the 'Edge of Love' actress was spending with her co-star and ex-boyfriend Matthew Rhys, and this put extra pressure on their relationship.

A source told Britain's The Sun newspaper: "Sienna broke the news at the weekend in a call from Prague. Things have been awkward for a while after she caught Rhys [Ifans] going through her text messages. She went mad and Rhys said he was looking for what he called 'incriminating evidence'."

Despite accepting Rhys' marriage proposal in March this year, Sienna says she has outgrown the relationship and the couple have already told friends they are taking a break from each other.

Rhys proposed to Sienna three times before she accepted, but sources claim she was never sure about tying the knot with him.

Another source said: "Sienna only accepted Rhys' proposal the third time because she really loves him and didn't want to lose him, despite feeling unready for marriage. He sensed that and became increasingly jealous and possessive of her."

In a bid to win Sienna back, Rhys has reportedly composed a song called 'The Twits', based on Roald Dahl's book of the same name.