US President Barack Obama believes that holding military talks with Russia on Syria is an important next step and hopes they will take place very shortly, Secretary of State John Kerry said on Friday.
Russia, which is building up a military presence in Syria, was quick to say that Moscow was also ready for talks with the United States.
At a meeting in London with United Arab Emirates Foreign Minister Abdullah bin Zayed, Kerry said the US president hoped that talks would "help define some of the different options available to us as we consider next steps in Syria".
"Our focus remains on destroying ISIL (Islamic State militants) and also on a political settlement with respect to Syria, which we believe cannot be achieved with the long-term presence of (President Bashar al-) Assad," Kerry told reporters. "We're looking for ways in which to find a common ground."
The United States opposes Russia's support for Assad, and the Pentagon last year cut off high-level discussions with Moscow after its annexation of Crimea and intervention in Ukraine.
But Russia's buildup at Syria's Latakia airbase raises the possibility of air combat missions in Syrian airspace. Heavy Russian equipment, including tanks, helicopters and naval infantry forces, have been moved to Latakia, US officials say.
Earlier, a Syrian military source said that troops had started to use new types of air and ground weapons supplied by Russia.
Kerry said the United States wanted to find "a diplomatic way forward".
"Everybody is seized by the urgency. We have been all along but the migration levels and continued destruction, the danger of potential augmentation by any unilateral moves puts a high premium on diplomacy at this moment," he added.
Millions of Syrians have fled the four-year conflict and the UAE foreign minister said his country had taken more than 100,000 Syrian refugees over the last four years.
He said it was important to forge a political agreement in Syria and end the hardship of Syrian people. "It'll be very difficult to sustain the current situation," he added.