The Duke of Edinburgh returned to King Edward VII's hospital for recovery on Friday after his "successful" heart surgery at St Bartholomew's on Wednesday.
In a statement Buckingham Palace said: "Following the Duke of Edinburgh's successful procedure at St Bartholomew's Hospital on Wednesday, His Royal Highness has been transferred to King Edward VII's Hospital this morning.
"The Duke is expected to remain in hospital for continuing treatment for a number of days."
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WATCH: Prince Philip undergoes successful procedure for pre-existing heart condition
So far, Philip has spent 17 nights in hospital - his longest ever stay. He was initially admitted to the private King Edward VII's Hospital on February 16 as a precautionary measure after feeling unwell.
On 1 March, however, he was transferred by ambulance to St Bartholomew's Hospital in the City of London.
The Prince of Wales visited his father in hospital on 20 February, making a 200-mile round-trip from his home, Highgrove, in Gloucestershire.
And during an interview with Sky News on 24 February, the Queen and Prince Philip's youngest son, Prince Edward said that his father was "looking forward to getting out".
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The Duke retired from royal duties in 2017
Prince Philip has been treated for heart problems in the past and in 2011 was rushed to hospital by helicopter from Sandringham after suffering chest pains as the royal family were preparing for Christmas.
In the serious health scare, he was treated for a blocked coronary artery at Papworth Hospital in Cambridgeshire and underwent a minimally invasive procedure of coronary stenting.
The Duke, who is set to mark his 100th birthday on 10 June, has been residing at Windsor Castle with the Queen throughout the lockdowns.
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