Sienna Miller's previous film credits include Alfie and Casanova

The 25-year-old star, who plays Andy Warhol's muse Edie Sedgwick, admitted she was nervous about how the critics would rate it.

Factory Girl follows the life of Sixties fashion icon Sedgwick, who committed suicide at the age of 28.

The film, directed by George Hickenlooper, also stars actor Guy Pearce as Warhol.

Miller, wearing a vintage 1960s-style mini-dress covered in tassels, said she felt a "trepidation" about reviews.

I couldn't care less about Bob Dylan's reaction George Hickenlooper director

She added: "But Edie's brother saw it and said that he loved it and her husband thought that it was like her, so I feel like if those people are happy I don't really mind too much."

Last month Miller denied the film blames singer Bob Dylan for the death of Sedgwick, who took an overdose of barbiturates in 1971.

He reportedly tried to halt the release of the film claiming it defamed him.

Character Billy Quinn - who has a doomed affair with Sedgwick in the film - bears a physical likeness to Dylan, but is said to be a composite of Dylan, Doors star Jim Morrison and Rolling Stones frontman Mick Jagger.

Miller bears more than a passing resemblance to Sedgewick

Dylan's lawyers have said the portrayal is defamatory even though it does not use his name.

But Miller told The Observer: "It blames Warhol more than anyone."

At the premiere Hickenlooper said: "I couldn't care less about Bob Dylan's reaction.

"My research showed that they were involved with each other.

"Edie's brother said they were involved. I guess it's embarrassing for him but it's the story we told."

The film's writer, Captain Mauzner, said the Billy Quinn character was based in part on Dylan.

He added: "It's based in part on a lot of different rock and rollers, some made up.