Britain's Prince Philip was admitted to a hospital in London on Tuesday evening as "a precautionary measure" on the advice of his doctor, Buckingham Palace said Wednesday.
A palace spokesperson said the 99-year-old Duke of Edinburgh is "expected to remain in hospital for a few days of observation and rest" after feeling unwell.
British media reported, citing a royal source, that Prince Philip does not have a coronavirus-related illness and walked into hospital unaided on Tuesday evening.
The source added he travelled there by car and was not an emergency admission.
Philip retired from public duties in 2017 and rarely appears in public.
He has been staying with the Queen Elizabeth II at Windsor Castle since coronavirus restrictions were first introduced last year.
He spent four nights at a hospital in December 2019, where he was treated for a "pre-existing condition".
Earlier this month, the palace confirmed the Queen and Philip had both received their first dose of a coronavirus vaccine.
