Britain's Queen Elizabeth has honoured Prince Philip, the Duke of Edinburgh, with a knighthood.

Britain's Queen Elizabeth

Britain's Queen Elizabeth

The 89-year-old monarch presented her husband, 93, with a Knight of the Order of Australia medal at an investiture ceremony at Windsor Castle yesterday (22.04.15), which was attended by Alex Downer, Australia's high commissioner in the UK.

A statement from Buckingham Palace reads: "The Queen today invested the Duke of Edinburgh with the insignia of a Knight of the Order of Australia at Windsor Castle."

Prince Philip was put forward for the honour by Australian Prime Minister Tony Abbott and was announced as the recipient in January this year after the Queen agreed to his suggestion.

His citation said: "For three-quarters of a century, Prince Philip has served the Crown, and the wider Commonwealth. He served originally as an officer in the Royal Navy and then as a member of the Royal Family.

"He has served Australia with distinction and is patron of over 800 organisations."

However, according to the Daily Express newspaper, the Prime Minister has since come under fire in Australia with critics claiming the knighthood should have been bestowed on an Australian national instead.