US Secretary of State John Kerry spoke with King Salman in Jeddah on Sunday, along with the Saudi foreign, interior and defense ministers.

"I want to thank you for the many things that Saudi Arabia is working on with us to great effect," Kerry told Salman at the beginning of their closed-door meeting.

A US spokesman said Kerry provided an update of the situation on the ground in Syria after a "cessation of hostilities" was reaffirmed last week. "The secretary also gave an update on Libya," the spokesman said.

The monarch discussed "aspects of cooperation between the two countries and developments in the region and efforts in that regards," The official Saudi Press Agency (SPA) reported. Kerry also discussed cooperation in "fighting terrorism" with Crown Prince Mohammed bin Nayef, who is also interior minister.

SPA reported that Kerry had discussed "regional issues... mainly developments in Syria," with his Saudi counterpart, Foreign Minister Adel al-Jubeir.

The United States and Saudi Arabia, alongside Turkey and several other Western and Gulf states, support rebels fighting against Syrian President Bashar al-Assad, who has military backing from Russia and Iran.

Meetings in Vienna

On Monday, Kerry is due in Vienna to co-host a meeting on Libya alongside Italian Foreign Minister Paolo Gentiloni. Riyadh allies Cairo and Abu Dhabi have been supporters of the rival administration that continued to withhold its backing of a US and UN-supported unity government. The rivalry between administrations in Libya following the 2011 NATO-backed overthrow of longtime ruler Moammar Gadhafi has ensured fertile ground for lawlessness and the "Islamic State" terror group.

On Tuesday, Kerry and his Russian counterpart, Sergei Lavrov, will lead a gathering of the International Syria Support Group in Vienna. That group includes Arab League and European Union countries as well as Turkey, Iran and China. They are hoping to push the warring parties in Syria to respect a truce that has been in place since February but been fraught with violations on both sides.

The United States, with Russia and France, was also due to co-chair a meeting about Armenia and Azerbaijan's Nagorno-Karabakh conflict.

se/sms (AFP, Reuters, AP)