The Duke of Edinburgh was taken to the King Edward VII Hospital on Tuesday evening, as a "precautionary measure" on the advice of his doctor "after feeling unwell," the statement said.
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Philip, 99, is expected to remain in hospital for a few days of observation and rest, the statement added.
Along with the Queen, Philip received his Covid-19 vaccine last month. The royal couple have been staying at Windsor Castle, a palace around 30 miles west of London, during the pandemic which has pummelled the U.K.
The country has the worst outbreak in Europe with more than 4 million cases and 118,000 deaths recorded, according to health officials.
Philip, who retired from public duties in 2017, is the longest-serving royal consort in British history.
He married the then-Princess Elizabeth in 1947 and together they have four children — Prince Charles, born in 1948; Princess Anne, born in 1950; Prince Andrew, born in 1960; and Prince Edward, born in 1964 — along with eight grandchildren and nine great-grandchildren.
A former naval officer and keen polo player, Philip enjoyed robust health well into old age, but he has had a number of health issues in recent years.
In 2011, he was rushed to a hospital by helicopter from Sandringham after suffering chest pains and treated for a blocked coronary artery. In 2017, he spent two nights in the King Edward VII hospital and was hospitalized for 10 days in 2018 for a hip replacement.
He was last hospitalized in December 2019, when he spent four nights in hospital for what the palace said was planned treatment of a pre-existing condition, although it did not reveal what that condition was.
Philip was also forced to give up driving at the age of 97, after car accident in January 2019, which left the passengers of another vehicle with minor injuries, although he escaped unscathed. The following month, Buckingham Palace announced that he had voluntarily surrendered his driver's licence.
His career has been punctuated by the occasional gaffe and off-color comment; in 2015, he made headlines when he exasperatedly swore at a photographer.
The Associated Press contributed to this report.