After the U.S. government announced Friday that it would deploy ground troops to Syria to help allied forces fight the Islamic State group, Russia has warned that the latest move by the administration of U.S. President Barack Obama could trigger a “proxy war” in the Middle East. According to Russian Foreign Minister Sergei Lavrov, the current situation has amplified the need for co-operation between Washington and Moscow.

Russia’s remark came after White House press secretary Josh Earnest announced at a Friday afternoon news conference that fewer than 50 troops would go to Syria to “train, advise and assist” vetted opposition forces in fighting ISIS militants in the country. Many consider the decision to deploy American troops to Syria a major turnaround of previous positions, in which Obama vowed of “no boots on the ground” in the region.

The U.S. made the decision “unilaterally and without any reference to the Syrian leadership,” BBC quoted Lavrov as saying. “I am convinced that neither the United States nor Russia of course wants any kind of slide into a so-called proxy war. But to me it is obvious that this situation makes the task of co-operation between the militaries even more relevant.”

Although U.S.-led coalition forces have been conducting airstrikes against ISIS in Syria, the U.S. recently gave up its training efforts in the country and opted to provide equipment and arms to the rebels.

However, an American military official said Friday that Russia’s involvement in both Syria and Ukraine has forced the U.S. to refocus with actions and change its outlook to see Russia as an adversary rather than an ally.

Russia began airstrikes against ISIS in Syria on Sept. 30, and has long supported the government of Syrian President Bashar Assad. The U.S., on the other hand, has called on Assad to step down.