Prince Philip has undergone a successful procedure for a pre-existing heart condition, Buckingham Palace has announced.
Buckingham Palace said he would remain in hospital for treatment, rest and recuperation for a number of days.
The Duke of Edinburgh, 99, has already spent 16 nights in hospital.
The duke was being treated for an infection and moved to St Bartholomew’s Hospital in London on March 1 for tests and observation on his heart condition.
Buckingham Palace said the procedure took place on March 3.
In 2011, Prince Philip was taken to hospital by helicopter from Sandringham after suffering chest pains as the royal family was preparing for Christmas.
The prince was treated for a blocked coronary artery at Papworth Hospital in Cambridgeshire and had a stent fitted.
Queen Elizabeth’s husband, who turns 100 in June, travelled by car from Windsor to King Edward VII’s hospital in Marylebone, central London, on February 16 as a precaution after feeling unwell.
The exact reason for his initial admission was not disclosed, but it was not related to coronavirus.
On March 1, Buckingham Palace announced the prince had been transferred to Barts by ambulance.
St Bartholomew’s Hospital in the City of London is an NHS hospital and home to Europe’s largest specialized cardiovascular unit.
Prince Charles visited his father at King Edward VII’s Hospital, the weekend after his admission.
Members of the Royal Family, including the Queen, have continued with their official duties during Prince Philip’s hospital stay.
Camilla Parker gave an update on Prince Philip’s condition when she visited a Covid vaccination centre in Croydon on March 3.
When a volunteer asked about the duke, she said: “We heard today that he’s slightly improving. So, that’s very good news. We’ll keep our fingers crossed.”
Prince Philip has received treatment for other health conditions over the years, including a bladder infection in 2012 and exploratory surgery on his abdomen in June 2013.