Prince Charles visits father Philip in hospital

The Duke of Edinburgh has been under medical supervision for the past four days

Prince Charles arrives at King Edward VII Hospital in London to visit his father Prince Philip. AP

Prince Charles on Saturday visited the hospital where his father Prince Philip is being kept as a precaution after feeling ill.

Charles arrived at the back of the London hospital where Philip, the 99-year-old husband of Queen Elizabeth II, has spent four nights.

Philip, the Duke of Edinburgh, was admitted on Tuesday as a precautionary measure after feeling ill with an ailment that is not related to Covid-19.

He is expected to remain in hospital until next week, a royal source said on Friday.

Doctors were acting out of an abundance of caution and the duke remains in good spirits, the source said.

Both Philip and the 94-year-old queen received their first dose of the Covid-19 vaccine in January.

He spent four nights at the same hospital at the end of 2019 while being treated for an underlying health condition.

Philip is rarely seen in public. He stepped down from official engagements in August 2017 after completing more than 22,000 solo events and thousands more alongside the queen.

A former naval officer renowned for his sometimes brusque manner and humour, Philip married Elizabeth in 1947, five years before she became queen. He is now by far the longest-serving consort of any British monarch.