The British playwright Peter Shaffer, who wrote Equus and the multiple Oscar award wimning Amadeus, has died in a hospice in Cork after falling seriously ill last week.

His agent said that Shaffer died on Monday morning at 5.30am at Cork's Marymount Hospice, with his family by his side.

A statement from theatrical and literary agency Macnaughton Lord Representation 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.

“His great friend and American agent, Dennis Aspland remained with him in Ireland throughout his short illness.

“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.”

His agent said his close family and friends would like to thank the staff who “cared for him so well” at Bon Secours Hospital and Marymount Hospice.

Liverpool-born Shaffer's well-known works include The Royal Hunt Of The Sun, Black Comedy, Lettice And Lovage and Five Finger Exercise.

He spent much of his working life with the National Theatre in London, the director of which, Rufus Norris, said on Monday that: "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. The plays he leaves behind are an enduring legacy."

Daniel Radcliffe in a scene from Equus

Shaffer's agent Rupert Lord, said: “He was simply at the end of his life but delighted to have been able to celebrate his 90th birthday with friends and then, I think, decided it was time.”

His play Amadeus, which was about the strained relationship between Mozart and his less gifted admirer and tormented rival composer Salieri, was adapted for a big screen production starring Tom Hulce as Mozart and F. Murray Abraham as Salieri in 1984. The film won eight Oscars the following year, including best film and a screenwriting award for Shaffer.

Simon Callow, Felicity Kendal in Amadeus

Shaffer's 1973 play Equus, which tells the story of a psychiatrist who attempts to treat a young man who has a pathological fascination with horses, was revived in 2007 with Harry Potter star Daniel Radcliffe in his first substantial theatre role. Equus was also a successful film in 1977 starring Richard Burton and Peter Firth.