By Neil Smith BBC News entertainment reporter

Pinter said the bandage above his eye was the result of a fall

As a poet, screenwriter and author of more than 30 plays, he has dominated the English literary scene for half a century.

However, his outspoken criticism of US foreign policy and opposition to the war in Iraq undoubtedly make him one of the more controversial figures to be awarded this prestigious honour.

Indeed, the Nobel academy's decision could be read in some quarters as a selection with an inescapably political element.

"There is the view that the Nobel literature prize often goes to someone whose political stance is found to be sympathetic at a given moment," said Alan Jenkins, deputy editor of the Times Literary Supplement.

"For the last 10 years he has been more angry and vituperative, and that cannot have failed to be noticed."

Harold is now a fully paid-up member of the awkward squad - he really likes to get up people's noses Alan Jenkins Times Literary Supplement

However, Mr Jenkins insists that, though Pinter's political views may have been a factor, the award is more than justified on artistic criteria alone.

"His dramatic and literary achievement is head and shoulders above any other British writer.

"He is far and away the most interesting, the best, the most powerful and most original of English playwrights."

'Inspiration'

Pinter's contemporaries have been quick to salute the announcement, with Sir David Hare calling him "both an example and an inspiration to us all".

"He has blown fresh air into the musty attic of conventional English literature by insisting that everything he does has a public and political dimension."

Sir David Hare said Pinter's writing has a "political dimension"

"With his earliest work he stood alone in British theatre up against the bewilderment and incomprehension of critics," said Sir Tom Stoppard.

"The fact that he brought the theatre around the corner was a test of his character as well as his artistry."

Ian Rickson, artistic director of London's Royal Court Theatre, has added his tributes.

"Pinter's influence in world literature is extraordinary," he said. "His immersion in his art and his commitment to justice is immense."

Earlier this week it was announced that Pinter would act at the Court in Samuel Beckett's play Krapp's Last Tape as part of the English Stage Company's 50th anniversary celebrations next year.

According to Mr Jenkins, however, not everyone will whole-heartedly join the chorus of approval.

"I don't imagine Tony Blair will be all that thrilled, or his cabinet," he told BBC News.

"Harold is now a fully paid-up member of the awkward squad; he really likes to get up people's noses."

'Fearless'

"He's been fearless in the articulation of his views, and it's not won him many friends," said Michael Attenborough, director of the Almeida Theatre in Islington, north London.

"He's never been backwards in coming forward, and you could argue it has cost him in certain areas."

Guenter Grass won the Nobel Literature Prize in 1999

Speaking outside his London home on Thursday, Pinter - wearing a bandage on his head due to a recent fall - would not be drawn on the Nobel Academy's motivations.

"I've been writing plays for about 50 years, and I'm also pretty politically engaged," he told reporters.

"I'm not at all sure to what extent that fact had anything to do with this award."

Mr Attenborough, though, says he would be "amazed" if the prize was in recognition of its recipient's anti-war stance.

"I don't think there's any particular history in the award of bending over backwards to reward political commitment," he told BBC News.

The Nobel committee does have a history of acknowledging writers who stand against power.

Previous winners include Soviet dissident Alexander Solzhenitsyn, outspoken German writer Guenter Grass and Wole Soyinka, a caustic critic of Nigeria's military regime.

However, Susan Hollis Merritt, bibliographical editor of The Pinter Review: Collected Essays, said it would be "simplistic" to claim Pinter was "only" selected because of his political activism.