The emir’s office said in August that Sheikh Sabah suffered health setback while in Kuwait.

Kuwait‘s 90-year-old ruler Sheikh Sabah al-Ahmad al-Sabah has returned home after treatment in the United States, state news agency KUNA said.

On August 18, KUNA reported the emir had “recovered from a setback and is in good health”. It also cited a palace statement without specifying the nature of the “setback”.

Earlier that day, Iranian Foreign Minister Mohammad Javad Zarif wished Sheikh Sabah a “speedy recovery” after holding talks with officials from the oil-rich Gulf emirate.

The emir travelled to the US for a meeting with President Donald Trump which was cancelled when he was admitted to hospital.

Sheikh Sabah had a pacemaker fitted in 2000 and he underwent successful urinary tract surgery in the US in August 2007.

The Kuwaiti emir has ruled the US ally and OPEC oil producer since 2006 and steered its foreign policy for more than 50 years.

He has pushed for diplomacy to solve regional issues, such as the ongoing boycott of Qatar by four Arab nations, and hosted major donor conferences for war-torn nations like Iraq and Syria.