Russia and the United States have held fresh talks on ways of cooperating to end the devastating five-year war in Syria as intensive Assad regime air strikes killed at least 30 civilians in a town northeast of Damascus.
Moscow and Washington are seeking ways of brokering an end to a conflict that has killed more than 400,000 people, according to the United Nations, and has sent a wave of refugees streaming towards Europe.
In the latest diplomatic contact between the two powers, Russian Foreign Minister Sergei Lavrov and US Secretary of State John Kerry spoke by phone on Saturday (local time), Russia's foreign ministry said.
"They discussed ... the possibility of Russian-American cooperation in the fight against terrorist groups in Syria," the statement said.
The statement did not identify the groups more closely.
Russia, which supports dictator Bashar al-Assad, is conducting airstrikes against various armed groups that are opposed to his rule including Nusra Front - an offshoot of al-Qaeda - and Islamic State, which the Americans also oppose.
But Washington says Moscow is also targeting moderate rebel groups which are ideologically opposed to al-Qaeda and which are supported by the United States.
Fighting continued unabated in Syria with intensive strikes by the Syrian air force on Jayrud, northeast of Damascus, which killed 30 civilians a day after the reported execution of a Syrian air force pilot, a monitor and rebels said.
They said the raids targeted a medical centre, a school and a residential area in Jayrud, a heavily populated town that had been earlier spared heavy bombing after striking a local truce with the army.
It had become in that time a sanctuary for thousands of civilians fleeing heavy battles nearby.
The UK-based Syrian Observatory for Human Rights said scores were also injured in the aerial strikes as well as by shelling from army posts in the area.
A rebel spokesman said the strikes seemed to be in revenge for the killing of the air force pilot who parachuted near the town after his plane crashed on Friday.