US President Joe Biden paid tribute to the late Prince Philip on Friday as a "heck of guy" who "never slowed down" over his long life.
Speaking to reporters in the White House, the president said he and his wife Jill Biden sent condolences to Queen Elizabeth II.
"He was a heck of a guy," Biden said, praising the prince's service to Britain and the Commonwealth, and recalling the prince's "bravery" in World War II.
Biden also noted Prince Philip's charity work and being a "champion of the environment."
"I think he's going to be missed, particularly in the United Kingdom. Ninety nine years old and never slowed down at all, which I admire the devil out of," said Biden, who at 78 became the oldest person inaugurated as president in January.
Earlier, Biden issued a statement saying: "From his service during World War II, to his 73 years alongside the Queen, and his entire life in the public eye -- Prince Philip gladly dedicated himself to the people of the UK, the Commonwealth, and to his family."