Prince Philip has undergone a successful procedure for a pre-existing heart condition at St Bartholomew's Hospital, Buckingham Palace has confirmed.
The 99-year-old will now remain in hospital for "treatment, rest and recuperation for a number of days," the statement confirmed.
So far, Philip has spent 16 nights in hospital - his longest ever stay. He was initially admitted to private King Edward VII's Hospital on February 16 as a precautionary measure after feeling unwell. On Monday, however, he was transferred by ambulance to St Bartholomew's Hospital in the City of London.
WATCH: Buckingham Palace's hospital update on Prince Philip
In a statement at the time, Buckingham Palace announced: "The Duke of Edinburgh was today transferred from King Edward VII’s Hospital to St Bartholomew's Hospital where doctors will continue to treat him for an infection, as well as undertake testing and observation for a pre-existing heart condition.
"The Duke remains comfortable and is responding to treatment but is expected to remain in hospital until at least the end of the week."
Prince Philip, 99, has undergone a successful procedure for a pre-existing heart condition
Camilla, 73, said of the Queen's husband: "We heard today that he's slightly improving, so that's very good news. We'll keep our fingers crossed."
The Duke will celebrate his 100th birthday on 10 June
Prior to that, Philip's youngest son, Prince Edward, spoke about his father's condition. "He's a lot better, thank you very much indeed, and he's looking forward to getting out, which is the most positive thing, so we keep our fingers crossed," he told Sky News.
Asked whether Philip was frustrated to be in hospital, Edward laughed and replied: "Just a bit. I think that gets to all of us, and then you can only watch the clock so many times and the walls are only so interesting.
"We've had some brilliant and lovely messages from all sorts of people and we really appreciate that and so does he, I've been passing them on. It's fantastic, thank you."
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