Kerry and Lavrov
Kerry and LavrovReuters

Russian Foreign Minister Sergei Lavrov and U.S. Secretary of State John Kerry on Wednesday discussed "the need for decisive joint action" against the Al-Nusra Front, an Al-Qaeda-linked jihadist group in Syria, Lavrov's office said.

The pair talked by phone about the situation in Syria, "particularly the need for decisive joint action against the Al-Nusra Front, as Russia has constantly proposed," the Russian ministry said in a statement.

Russia last month floated a proposal for joint air strikes with the United States against jihadists in Syria but the offer was swiftly rejected.

The Pentagon said on May 20 that American forces "do not collaborate or coordinate with the Russians on any operations in Syria," adding that Washington and Moscow had separate military objectives there.

"Russian operations are supporting and enabling the Assad regime, and our focus is solely on degrading and defeating ISIL," Pentagon spokesman Jeff Davis said, referring to the principal jihadist group in Syria, the so-called Islamic State or ISIS.

The United States and Russia are partners in the so-called Vienna diplomatic process of the International Support Group for Syria, which met last month but made no notable progress.

A cessation of hostilities between the government and non-jihadist opposition groups took effect on February 27 but it has failed to build into a durable truce.

One factor in the complex equation has been Moscow's air campaign in support of its Damascus ally.

It has been criticized for targeting non-jihadist rebels as well as Al-Qaeda and ISIS. At one point, in fact, France said that 90% of Russian airstrikes have targeted "moderate" rebels in a bid to prop up Syrian President Bashar Al-Assad. 

On Wednesday, Russian officials said a 48-hour truce in the town of Daraya had been agreed "with the leadership and the American side" to help deliver aid to the population.

At least 280,000 people have been killed and more than half of Syria's population have fled their homes since the conflict erupted in 2011.

AFP contributed to this report.