Prince Philip, Queen Elizabeth’s 99-year-old husband and Duke of Edinburgh, was admitted back to a private hospital in London after successfully undergoing a heart procedure on Friday, AFP reported, referring to Buckingham Palace.

An immediate cause of concern in the UK was the health of Philip, who was returned from a cardiac unit back to the hospital in hopes of a faster recuperation.

The aged prince had earlier been brought to the specialist centre located near St Paul’s Cathedral, from whence he was moved back to the hospital in an NHS ambulance with tinted windows at around 12.00 GMT.

King Edward VII’s Hospital in central London’s Marylebone district is the private institution where Prince Philip will be kept for now.

“The duke is expected to remain in hospital for continuing treatment for a number of days,”, royal officials were quoted by AFP as saying.

The Duke of Edinburgh and Queen both received their first jab of the COVID-19 vaccine in the Windsor castle in January.

Prince Philip’s daughter-in-law Camilla said earlier this week that the nonagenarian was “slightly improving“.

The prince’s youngest son Edward had said that his father could not wait to leave the hospital.

The issue comes amidst a scathing transatlantic war of words between Duchess of Sussex Meghan Markle and the Royal Family, whose soon-to-be released interview with US talk show host Oprah Winfrey is set to be discussing her troubled times staying with the Royal Family.