Closed-door talks between the United States and Russia on the Syrian conflict were "constructive and productive," US Secretary of State John Kerry said Friday in Vienna.
Kerry, who met earlier Friday with foreign ministers from Turkey and Saudi Arabia before talks with Russian Foreign Minister Sergei Lavrov, said the meetings generated ideas that "have a possibility of ultimately changing the dynamic" in the Syrian crisis.
He offered no details.
The powers discussing Syrian issues could reconvene as early as October 30, Kerry said, and could include representatives from a larger group of countries from both Europe and the Middle East.
There are currently no plans to involve Iran in the discussions, US State Department spokesman Mark Toner said later Friday.
Russia and the United States have been conducting separate bombing campaigns in war-torn Syria - Russia in support of al-Assad and the US in support of rebels trying to overthrow the regime.
Washington and Moscow signed a memorandum of understanding this week to communicate more closely about military flights in the region to minimize the risks of an accidental clash between their forces.
Russia and Jordan agreed to coordinate airstrikes and other military actions in Syria, Lavrov said Friday after a meeting with his Jordanian counterpart in Vienna.
It was unclear whether the Russian-Jordanian coordination would follow a similar framework to the US memorandum, or extend to coordinated attacks against Islamic State militants.
Russia has been carrying out airstrikes since last month in Syria to support President Bashar al-Assad.
Jordan is part of a US-led coalition carrying out airstrikes against Islamic State forces. Unlike Russia, Jordan supports rebels fighting to oust al-Assad.
Middle Eastern powers such as Turkey and Saudi Arabia, as well as Western governments, have called for al-Assad to resign so a transitional government could be formed and the four-year civil war be brought to an end.
The Turkish and Saudi foreign ministers held separate talks with Lavrov Friday.
Al-Assad, who has run Syria for more than 15 years since succeeding his late father, is Russia's closest ally in the Middle East. He visited Moscow this week for surprise talks with Russian President Vladimir Putin in his first official trip outside Syria since the civil war began.
Putin said Thursday that al-Assad would allow Russia to support Syrian opposition groups as part of the peacemaking process, including supplying aid to moderate militants fighting Islamic State.
Kerry said Thursday in Berlin that Russia and Iran, another close ally of the Syrian government, agreed that a political process was essential to peace.
"One thing stands in the way of being able to rapidly move to implement that, and it's a person called Assad - Bashar al-Assad," Kerry said.
More than 250,000 people have died in the Syrian conflict, according to estimates by the United Nations. The conflict broke out in 2011 as protests against al-Assad's rule devolved into violence after a heavy-handed crackdown by authorities.
By Peter Spinella
