Prince Philip, the Duke of Edinburgh and Queen Elizabeth II’s husband of more than 70 years, has died at the age of 99.

The British royal family’s official Instagram account broke the sad news at midday on Friday local time, revealing that Prince Philip had passed away peacefully that morning at Windsor Castle. He was just two months away from his 100th birthday.

“It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh,” the Instagram post said.

“His Royal Highness passed away peacefully this morning at Windsor Castle. The Royal Family join with people around the world in mourning his loss.”

The Instagram post said “further announcements” will be made in “due course”.

The Duke of Edinburgh had battled a range of health issues in recent years and was released from hospital only three weeks ago, having contracted an infection and having had surgery for a heart condition that required a month’s hospitalisation. The royal family’s statement did not specify the cause of his death.

Prime Minister Scott Morrison paid tribute to the prince, saying that he “embodied a generation we will never see again”.

“Through his service to the Commonwealth he presided as patron or president of nearly 50 organisations in Australia,” the Prime Ministerial Office’s statement said.

“Given his own service, Prince Philip also had a strong connection with the Australian Defence Force. For 65 years, The Duke of Edinburgh’s Award scheme has encouraged over 775,000 young Australians to explore their leadership potential. Forty thousand young Australians are currently participating in the program.

“Australians send our love and deepest condolences to her Majesty and all the Royal family. The Commonwealth family joins together in sorrow and thanksgiving for the loss and life of Prince Philip. God bless from all here in Australia.”

The statement added that flags would be lowered in Australia in honour of the prince. Prince Philip had visited Australia more than 20 times during his life.

Others have taken to social media to pay their respects, with Queensland Premier Annastacia Palaszczuk writing on Twitter: “I send condolences on behalf of all Queenslanders to Buckingham Palace regarding the death of HRH The Duke of Edinburgh. The Duke of Edinburgh is a much loved and respected member of the Royal Family and will be remembered fondly in Queensland.”

Former Australian prime minister Julia Gillard spoke of Philip’s “sense of fun”. She wrote on Twitter: “I have fond memories of spending time with Prince Philip during his visit to Australia at the time of CHOGM in Perth. While a man of duty, he had a sense of fun. His loss will be mourned by the Queen, his family and millions around the world.”

Meanwhile, British journalist Piers Morgan remembered the prince as “a truly great Briton who dedicated his life to selfless public duty”. “A very sad day for our country,” he wrote. “Thank you, Sir.”