RIYADH: World leaders headed to Saudi Arabia Saturday to offer condolences following the death of King Abdullah.

Since Abdullah took the throne in 2005, Saudi Arabia has been a prime Arab ally of Washington, and last year joined the coalition carrying out air strikes against the Islamic State jihadist group.

Other dignitaries arrived in Riyadh on Saturday to pay respects, including Iranian Foreign Minister Mohammad Javad Zarif, on a rare visit to the regional rival.

British Prime Minister David Cameron, Prince Charles and French President Francois Hollande were among other leaders expected to fly in to offer condolences. Abdullah was a cautious reformer who led the Gulf state through a turbulent decade in a region shaken by the Arab Spring uprisings and Islamic extremism.

He died on Friday at the age of about 90 after being hospitalised with pneumonia. World leaders have praised the king as a key mediator between Muslims and the West, but campaigners criticised his rights record and urged Salman to do more to protect freedom of speech and women's rights.

Gulf rulers, and leaders including Turkish President Recep Tayyip Erdogan and Pakistani Prime Minister Nawaz Sharif, were among those who attended Abdullah's traditionally simple funeral at Riyadh's Imam Turki bin Abdullah mosque on Friday.

Africa was also represented, with Sudanese President Omar al-Bashir and Ethiopian Prime Minister Hailemariam Desalegn.

President Ali Bongo Ondimba of Gabon and other leaders from the continent arrived on Saturday to pay respects.

On Friday the late king's body, wrapped in a cream-coloured shroud, was borne on a litter by members of the royal family wearing red-and-white checked headgear.

The body was quickly moved to nearby Al-Od public cemetery and buried, in a grave marked only by a book-sized plain grey stone.

Palestinian President Mahmud Abbas and Malaysia's Prime Minister Najib Razak arrived later to deliver condolences, as did Iraqi President Fuad Masum.-AFP