His son William outlined the work of Sheikh Sabah as a diplomat in the Middle East.
The Prince of Wales wrote in a letter dated 29 September: “Your Excellency, I am deeply saddened to learn of the death of your beloved brother, His Highness Sheikh Sabah Al Ahmad Al Jaber Al Sabah, and I am most especially Hearty wanted to congratulate. Sympathy to your family, your family and the people of Kuwait state at a very sad time.
“As a leader, and a humanist, the late Amir’s wisdom and commitment to peace and stability was greatly admired, and I can well imagine how deeply his loss was felt by so many people Will be done.
“I will always cherish the most special and affectionate memories of his heavenly greatness, whose grace will never be upon me in all these years.
“I can only offer your latest condolences, with heartfelt wishes, and assure my supremacy my commitment to the bonds of friendship and co-operation that have existed between our two countries for so long. ”
Prince Charles visited Kuwait twice on behalf of the British government.
He traveled the country for the first time during an important tour of the Persian Gulf with Princess Diana in 1989.
READ MORE: Prince Charles branded ‘Prince Mang’ among 100 ruined eggs
During his visit, he had an audience with Sheikh Saba as well as lunch.
Prince of Wales returned to Kuwait in 2007 with Camilla, Duchess of Cornwall.
The Duke of Cambridge came to the Middle Eastern country for the first time during a four-year solo tour which also brought him to Oman.
William expressed grief over the death of the 91-year-old emir: “I am sorry to hear about the demise of His Highness Sheikh Sabah Al Ahmad Al Jaber Al Sabah.”
“I had the privilege of meeting His Excellency during a visit to Kuwait last year and I know that he will be remembered for his global humanitarian efforts and commitment to regional peace.
“I express my sincere condolences to the Kuwaiti people as they mourn Her Majesty’s death.”
Prince Charles and Prince William’s messages come after the Queen offered her sympathy to the Kuwaiti people in a private letter addressed to Sheikh Nawaf al-Ahmad al-Sabah’s brother.
Recalling Sheikh Sabah’s state visit to Britain in 2012, Rani said: “Your distinguished brother dedicated his life to the service of the Kuwait state and especially to his colleagues and friends.
“He will be long remembered by all who work for regional stability, understanding between nations and between beliefs and for humanitarian cause.
“I took a deep step towards the United Kingdom and its memorable state visit in November 2012.”
Sheikh Saba died at the Mayo Clinic in Rochester, Minnesota, where he was recovering after surgery in July.