Magical Potter teaser revealed

Daniel Radcliffe as Harry Potter in the trailer

Harry Potter fans have been given their first glimpse of the eagerly-awaited movie about the teen wizard.

Warner Brothers have put up their first film trailer of Harry Potter and the Philosopher's Stone, starring Daniel Radcliffe as the young magician.

The film is based on the first of JK Rowling's four Potter best-sellers and is due for release in November.

Beginning with the words "There's no such thing as magic..." the trailer shows dozens of owls bursting out of the Warners Brothers logo.

Julie Walters also stars

The Hogwarts Express is seen steaming through the countryside, while Hogwarts School is a spectacular castle filled with burning torches.

Robbie Coltrane, as the giant Hagrid, is seen smashing down a door.

"We are expecting a phenomenal demand," a spokeswoman for Warner Brothers said.

Billy Elliot actress Julie Walters and veteran actor Richard Harris also star in the movie.

Radcliffe - who has acted on TV - is joined by newcomers Emma Watson, 10, and Rupert Grint, 12.

They play Ron and Hermione, Harry's best friends at Hogwart's school.

Warner Brothers are yet to decide on a final version of a trailer for cinema-goers.

'Elated'

Meanwhile on set, filming has had to be extended to mid-July due to delays over bad weather.

Harry Potter stars Grint (top), Radcliffe and Watson

Warner Bros has had to approach Radcliffe's local London council to ask for his original work permit to be extended.

Work on the movie - which is expected to be one of the biggest box office hits of 2001 - began in September last year.

Finding the right children to play the principal parts was a secretive and time-consuming task, particularly for director Christopher Columbus

Having made his choice, Columbus commented: "There were times when we felt we would never find an individual who embodied the complex spirit and depth of Harry Potter.

"Then, Dan walked into the room and we all knew we had found Harry. We were equally elated upon meeting Emma and Rupert."

Radcliffe most recently portrayed young David in the BBC's David Copperfield adaptation and will be seen later this year in the John Boorman film The Tailor of Panama.

Watson and Grint have acted in school plays.