The Duke was moved to St Bartholomew's Hospital days ago.
Prince Philip has undergone a "successful procedure" on a pre-existing heart condition for which he is currently being treated in hospital, Buckingham Palace have confirmed.
In a statement, Buckingham Palace said: "The Duke of Edinburgh yesterday underwent a successful procedure for a pre-existing heart condition at St Bartholomew's Hospital.
"His Royal Highness will remain in hospital for treatment, rest and recuperation for a number of days."
The Duke of Edinburgh has been been in King Edward VII's Hospital in London since February 16, a move described by Buckingham Palace as a precautionary measure with the 99-year-old feeling unwell.
According to royal sources, Philip's admission to hospital is being classed as non-serious. The Duke was admitted to hospital previously just before Christmastime in 2019.
He was said to have been admitted as a "precautionary measure" on the advice of his doctor.
Buckingham Palace confirmed the news in a statement at the time, saying: "The Duke of Edinburgh travelled from Norfolk this morning to the King Edward VII Hospital in London for observation and treatment in relation to a pre-existing condition.
"The admission is a precautionary measure, on the advice of His Royal Highness's doctor."
