Saudi Arabia warned Thursday that any military cooperation between the United States and Russia in Syria must help advance a political transition to end the war without Bashar al-Assad in power.

Foreign Minister Adel al-Jubeir told reporters he was ready to welcome US-Russian cooperation as US Secretary of State John Kerry headed to Moscow for talks on ending Syria's five-year war.
"With regards to the Russian-American cooperation in the fight against terrorism: this is something we had asked for," Jubeir told reporters following meetings at the United Nations.
But he added: "The key is really to move the situation in Syria along a political process."
The Washington Post reported that Kerry will propose setting up a joint command and control center to direct air strikes against the Islamic State and other jihadist groups, during his talks with President Vladimir Putin.
The Saudi foreign minister said Syria must move forward on a political transition that provides for an interim governing council with full power to manage state affairs and "lead to a new Syria without Bashar al-Assad in it."
"Anything that helps move the process in that direction is something that we would welcome," he added.
Russia had repeatedly called on the United States and other countries to cooperate more closely to defeat the Islamic State group and other jihadists in Syria.
Cooperation with Moscow has long been viewed with suspicion, as it would amount to acceptance of Russia's backing for the Assad regime.
Saudi Arabia is supporting various rebel groups fighting the Damascus regime, some of whom have close ties with the Al-Qaeda-affiliated Al-Nusra Front and are not considered moderates.
Under a UN plan, the political transition in Syria is to begin on August 1, with the formation of an interim body followed by the drafting of a new constitution and elections 18 months later.
But the fate of Assad remains unresolved, with the opposition demanding that he must leave power immediately.