Sadie: Sienna is new muse

Sienna Miller has already ousted Sadie Frost from her throne as one half of Britain's hottest A-list couple. But she is not content simply with landing Frost's ex, Jude Law. Now the 22-year-old has replaced 37-year-old Frost as the muse of British couturier Matthew Williamson.

Speculation that she was to become Williamson's new "girl" began earlier this year, when Miller was snapped at the Golden Globe Awards in LA wearing a £6,000 fuchsia silk dress from his not-yet-unveiled New York collection. He then asked her to be the face of his new perfume but she had filming commitments.

Now Miller's look is said to have inspired Williamson's designs for London Fashion Week this month.

Today Frost tells InStyle magazine: "I used to be Matthew's muse, but Sienna is now, which is funny." Williamson is a friend and neighbour of Frost's in Primrose Hill. "When I first went to New York, Sadie and Plum Sykes hosted a party for me, which helped to launch me there," he said. "These women have been there for me since day one. The relationship is genuine."

Miller and Frost are not the first to have been granted the honour of being Williamson's muse - others include Jade Jagger and Gwyneth Paltrow - and they are unlikely to be the last.

Frost insists she bears no grudge. "I saw [Matthew] the other week and gave him a big hug," she says. "I understand the politics."

Speaking recently, Frost admitted she is "happier than ever" with her boyfriend, 22-year-old flamenco guitarist Jackson Scott. "When you have been married to someone for a long time and you split up, you discover your independence. Now I feel more in control of my life," she said.

She even hugged Miller when they met by chance at Glastonbury.