The 64 year-old British-born star of classic musicals The Sound of Music and Mary Poppins has been unable to sing since undergoing throat surgery in 1997.

But Andrews, who is currently making a film version of Noel Coward's 1951 play Relative Values, has told the Los Angeles Times that she has not given up the struggle to regain her voice.

"It's been a tough two years. I can't pretend it's been easy. But I'm a very optimistic lady. I think I will sing again. I hope to," she said.

Born in Surrey, Julie Andrews shot to international stardom with 1964's hugely successful family musical Mary Poppins and The Sound of Music in 1965.

She was also in the original Broadway versions of Camelot and My Fair Lady and she won a Tony Award nomination for the stage version of Victor/Victoria.

But in 1997, after missing more than 30 performances of the show, she quit for good to have surgery on non-cancerous nodules in her throat.

In the summer of 1998 she made a tentative step back to singing when she recorded the vocal part of Polynesia The Parrot for the London stage show Doctor Dolittle.

But despite not having taken on any further singing projects, Andrews is determined not to let the grass grow under her feet.

In Relative Values, she plays the part of the widowed English countess Felicity. She stars alongside Colin Firth, Jeanne Tripplehorn, William Baldwin and Sophie Thompson.