Prince Philip, husband of Britain's Queen Elizabeth II, was admitted to hospital for the "assessment and treatment of a chest infection," officials said on Friday, according to dpa. Buckingham Palace, the seat of Britain's monarchs, said in a statement that the 86-year-old Duke of Edinburgh was admitted to London's private Edward VII hospital on Thursday. "His Royal Highness's programme of engagements for the weekend have been cancelled," the statement said. Prince Philip on Wednesday evening had been due to attend a service honouring Sir Edmund Hillary, the late conqueror of Mount Everest, but failed to attend because of his illness, Buckingham Palace said. According to British media reports, the Duke of Edinburgh walked into the clinic and was sitting up and working on his correspondence on Thursday while in hospital. It is expected that he will remain in hospital over the weekend. His last public engagement was last Thursday when he attended the formal send-off of French President Nicolas Sarkozy at Windsor Castle with the queen. Prince Philip is said to be in robust health despite his advanced age, but during the last years there was speculation on alleged heart problems. The Duke of Edinburgh, who was born as Prince of Greece and Denmark on Corfu, has been married to the queen since 1947. He renounced his royal title and became a naturalized British subject in 1947. During World War II he served in the British navy. He is known both for his charms and sense of humour as well as his tendency to create embarrassments. The prince made headline news most recently in connection with the inquest into the death of Princess Diana and her lover, Dodi al-Fayed. Egyptian businessman Mohamed al-Fayed claimed that Diana and his son were murdered on Prince Philip's orders. In his summary, the presiding judge told the jury there was no evidence favouring this theory.