British playwright Peter Shaffer, who won an Oscar for his film adaptation of "Amadeus", one of his most celebrated stage dramas, died on Monday aged 90, his agent said.

"It is with great sorrow that we must announce the death of our friend and client, Sir Peter Shaffer CBE whilst on a visit to Ireland with friends and family," Rupert Lord said on his agency's website.

Shaffer died at 5:30 am (0430 GMT) at a hospital outside Cork in southern Ireland following a short illness, Lord said.

"Peter was one of the true greats of British theatre as well as a wonderful friend, wickedly funny man and sparkling raconteur whose lifelong passion for his own art was matched by his love for music, painting and architecture," said Lord.

Shaffer won the Oscar in 1985 for the adaptation of "Amadeus", his drama about composer Antonio Salieri's jealous fixation with Wolfgang Amadeus Mozart. It was one of eight Oscars which the film won that year.

He also received an Academy Award nomination in 1978 for the screenplay of "Equus", his 1973 stage play about a psychiatrist treating a young man fascinated by horses.

His other plays include "Lettice and Lovage" and "The Royal Hunt of the Sun".

"He had been struggling with his health for some time but was both determined and delighted to have been able to celebrate his 90th birthday in Ireland last month with close family and friends," said Lord.

- Twin also famous screenwriter -

Shaffer was born to a Jewish family in Liverpool, northwest England, and educated in London before studying history at the University of Cambridge.
He was conscripted to work in the coal mines during World War II.

He was the twin of Anthony Shaffer, the screenwriter and playwright whose screenplays included the Alfred Hitchcock film "Frenzy", the British cult thriller movie "The Wicker Man" and Agatha Christie's "Death on the Nile". He died in 2001.

Peter Shaffer also received multiple Tony, Olivier and Golden Globe awards.

He was made a Commander of the Order of the British Empire (CBE) in 1987 and knighted in 2001.

Much of his working life was linked to the National Theatre in London, for which several of his plays were written and first produced.

"Peter Shaffer was one of the great writers of his generation and the National Theatre was enormously lucky to have had such a fruitful and creative relationship with him," said its director Rufus Norris.

"The plays he leaves behind are an enduring legacy."

The British Film Institute said it was saddened to hear of his death.

A private funeral will be held in London in the coming days.

"Details of a memorial ceremony will be announced in due course," Lord added.

Soource; AFP