Prince Philip has been admitted to hospital as the Queen arrived in Norfolk for the royals' Christmas break.

Buckingham Palace said the 98-year-old Duke of Edinburgh had been admitted to hospital for treatment relating to a pre-existing condition.

Prince Philip left Sandringham, where he spends much of his time since retiring, to attend the King Edward VII Hospital in London on Friday morning.

The announcement came as the Queen arrived at the Norfolk estate after travelling from the capital.

A Buckingham Palace statement said: "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 Duke is expected to be in hospital for a few days, meaning he could miss the Royal family's Christmas Day gathering and church service.

As Prince Philip has continued late into his 90s, concerns for his well-being have increased following a number of health scares.

Abdominal surgery, bladder infections and a blocked coronary artery have seen him admitted to hospital on a number of occasions.

The Prince suffers from arthritis in his right wrist, and broke a bone in his ankle playing polo. He also developed synovitis, a rheumatic condition of the tendon in the hand, after a polo fall.

In late 2011, the Duke, then aged 90, was rushed to hospital by helicopter from Sandringham after suffering chest pains as the Royal Family were preparing for Christmas.

In the serious health scare, he was treated for a blocked coronary artery at Papworth Hospital in Cambridgeshire and underwent a minimally invasive procedure of coronary stenting, and spent Christmas Day and Boxing Day in hospital.

And in the midst of the Queen's Diamond Jubilee celebrations in June 2012, the Duke was forced to miss the majority of the festivities after falling ill with a bladder infection.

The Duke has also made several trips to the King Edward VII's private hospital, in Marylebone, in recent years.

In June 2017, the Duke spent the day at Royal Ascot, where the hot weather meant the dress code in the Royal Enclosure was relaxed for the first time.

That same evening, he was admitted to King Edward VII's Hospital as a precautionary measure, for treatment for an infection arising from a pre-existing condition.

He missed the State Opening of Parliament, with the Prince of Wales stepping in to accompany the Queen, before being discharged after a two-night stay.

In March 2018, he missed the Maundy Thursday service with the Queen because of a problem with his hip and a few days later, in April, Prince Philip was admitted to hospital ahead of a planned hip replacement.

The Duke left hospital 10 days later.

In January this year, Prince Philip was involved in a car crash when the Land Rover Freelander he was driving flipped over after colliding with another car near the Sandringham estate.