The husband of Queen Elizabeth was admitted to the King Edward VII Hospital in London on February 17 after feeling unwell.
According to a statement issued by the Buckingham Palace on the health of the Duke of Edinburg, Prince Philip would undergo treatment until at least the end of the week.
It said the Duke remains comfortable and is responding to treatment.
Prince Charles last week visited his father in the hospital where, according to British tabloids, they discussed future of the British royal family.