World’s longest reigning monarch admitted to hospital

The Sultan of Brunei was admitted to the National Heart Institute in Kuala Lumpur

The sultan of Brunei Hassanal Bolkiah has been admitted to hospital (AFP/Getty)

Brunei's Sultan Hassanal Bolkiah is currently resting in a Kuala Lumpur hospital after experiencing fatigue during a summit of Southeast Asian leaders, according to Malaysia's Prime Minister.

Prime Minister Anwar Ibrahim, who currently chairs the Association of Southeast Asian Nations, confirmed that the 78-year-old Sultan had been admitted to the National Heart Institute in Kuala Lumpur. He made the statement in response to a question during a press conference.

"He's a little bit tired and resting," Anwar said, without providing further details about the Sultan's condition or the length of his stay in the hospital.

Malaysia's Prime Minister Anwar Ibrahim (right) greets Brunei's Sultan Hassanal Bolkiah (Reuters)

The sultan has ruled the oil-rich nation of Brunei, on the island of Borneo, since 1967. He was once the world's richest man and remains hugely popular, despite holding a firm grip on power in the country of nearly half a million people.

Under his rule, Brunei gained full independence from Britain and oversaw a rise in living standards to among the highest in Asia.