UAE’s long-ailing leader Sheikh Khalifa bin Zayed has died aged 73

The United Arab Emirates’ long-ailing ruler, Sheikh Khalifa bin Zayed Al Nahyan, has died, the government’s state-run news agency announced in a brief statement.

He was 73.

The UAE’s ministry of presidential affairs announced a 40-day period of mourning and a three-day suspension of work in all ministries and the private sector beginning on Friday.

Flags will be flown at half-mast.

Sheikh Khalifa had long ceased being involved in the day-to-day running of the country, with his brother, Abu Dhabi’s Crown Prince Mohammed bin Zayed, seen as the de facto ruler.

There was no immediate announcement about a successor, although Sheikh Mohammed is in line to inherit the top post.

Sheikh Khalifa, who had rarely been seen in official photos or at public events for years, succeeded his father and the UAE’s founder Sheikh Zayed in 2004.

He suffered a stroke a decade later, keeping him largely out of public sight.

The world’s tallest tower in the UAE’s emirate of Dubai is named the Burj Khalifa after the ruler, whose oil-rich emirate helped bail Dubai out during a financial crisis.