Kuwait’s Emir Sheikh Sabah al-Ahmad al-Sabah died on Tuesday aged 91.
The country will now spend 40 days in mourning.
“With hearts filled with pain and sadness for the Kuwaiti people… the Cabinet mourns Sheikh Sabah al-Ahmad al-Jaber al-Sabah who died in the US on Tuesday,” an official statement said.
In August 2019, Sheikh Sabah suffered an unspecified medical condition that required surgery, after which he was flown to a US hospital in July 2020.
Known as the “wise man of the region”, he was the architect of modern Kuwait’s domestic and foreign policy.
Sheikh Sabah kept strong ties with the US, which led a coalition that ended Iraq’s 1990-91 occupation.
He always tried to peacefully influence relations between Kuwait’s bigger neighbours by forging close ties with Saudi Arabia, rebuilding links with former occupier Iraq and keeping open dialogue with Iran.
United Nations secretary-general Antonio Guterres praised the emir as “an extraordinary symbol of wisdom and generosity, a messenger of peace, a bridge builder”.
The cabinet has announced his brother Crown Prince Sheikh Nawaf al-Ahmad al-Sabah as the new ruler.
Sheikh Nawaf, 83, will be sworn in today.