Russian foreign minister Sergei Lavrov warned Friday that the Syrian conflict could turn into a "proxy war" between Russia and the U.S.

"I am convinced that neither the United States nor Russia of course want any kind of slide into a so-called proxy war," Lavrov told reporters after talks on the Syrian crisis in Vienna, according to Reuters.

"But to me it is obvious that this situation makes the task of co-operation between the militaries even more relevant," he added.

Lavrov's "proxy war" warning comes after the U.S. announced that it will deploy about 50 special operation forces in northern parts of Syria to advise and assist opposition forces fighting the Islamic State group, Press TV reported.

"The US decision is unilaterally and without any reference to the Syrian leadership," the Russian foreign minister said, according to BBC News. It will be U.S. military's first-ever ground deployment on Syrian grounds.

The negotiations in the Austrian capital failed to find an agreement on the fate of Bashar al-Assad's regime, Egyptian Streets reported. However, delegates from key countries, including Russia and the U.S., agreed on the need for a U.N.-brokered ceasefire between the regime forces and moderate opposition rebel groups in the war-torn country.

"[US Secretary of State] John Kerry said much about the Syrian development, about the suffering of the Syrian people, about how much blood has been shed there and how many people have been driven out of their homes," Lavrov said, according TASS. "We want to stop this situation and prevent terrorists from getting power in the country."