The cause of his death was not immediately disclosed. The emir was admitted to hospital late last month due to what the state news agency described at the time as an emergency health problem but said that he was in a stable condition.

Crown Prince Sheikh Meshal al-Ahmad al-Sabah, 83, who has been Kuwait's de facto ruler since 2021, when the frail emir handed over most his duties, was named as Sheikh Nawaf's successor.

Sheikh Nawaf became emir in September 2020 following the death of his brother, Sheikh Sabah, who had ruled for more than a decade and shaped the state's foreign policy for over 50 years.

Sheikh Nawaf was seen by diplomats as a consensus builder even though his reign was marked by an intense standoff between the government and elected parliament, which had hindered key structural reforms in the oil rich Gulf state. In recent months, consensus returned between the government and the parliament.

Kuwait, holder of the world's seventh-largest oil reserves, borders Saudi Arabia and Iraq, and lies across the Gulf from Iran. It was invaded and occupied by Iraq in 1990, sparking the first Gulf war several months later in 1991 when the United States and other nations defeated Iraq and liberated Kuwait.

Since he took over in 2020, Sheikh Nawaf maintained a foreign policy that balanced ties with those neighbours, whilst domestically eight governments were formed under his rule.

Under Kuwait's constitution, the crown prince automatically becomes emir but assumes power only after taking an oath in parliament. The new emir has up to a year to name an heir.

Analysts and diplomats say that Sheikh Nawaf, and his crown prince Sheikh Meshal, both appeared to align Kuwait more closely with regional powerhouse Saudi Arabia.