European Union foreign policy chief Federica Mogherini said Monday that Russia's military action in Syria is a "game-changer" that has "some very worrying elements."
Mogherini told reporters ahead of a meeting of EU foreign ministers in Luxembourg that actions taken against Islamic State militants have to clearly be carried out against the group and other terrorists defined by the United Nations.
Russia has faced Western criticism that its air campaign in Syria is targeting opponents of President Bashar al-Assad, a Russian ally, and not the Islamic State group.
Mogherini said she believes the EU, Russia and the United States have common ground in Syria based on U.N. Security Council resolutions and a U.N. framework, but that their action must be coordinated.
Otherwise, she said, there are "extremely dangerous" risks particularly militarily.
Mogherini expected the ministerial meeting to cover what the EU can contribute to pushing forward the process to find a political resolution to the crisis in Syria that has killed 240,000 people since March 2011.
She said the process should include everyone who has a role in the conflict and transition, with an outcome determined mostly by the international community, the region and mostly by Syrians.
On Sunday, U.S. President Barack Obama told CBS television's 60 Minutes that Russia's intervention in Syria is aimed at saving Assad's government.
"Syria was Russia's only ally in the region," Obama said. "And today, rather than being able to count on their support and maintain the base they had in Syria, which they've had for a long time, (Russian President Vladimir) Putin now is devoting his own troops, his own military, just to barely hold together by a thread his sole ally."
Putin said in an interview with Russian media on Saturday that the goal of his military's action in Syria is to "stabilize the legal government and create the right conditions for reaching a political compromise."
Last week, the U.S. Defense Department scrapped its failed program to train and equip moderate Syrian rebels to fight the Islamic State group.
Obama told 60 Minutes he was skeptical from the very start that it would work. He said part of his strategy in Syria is to try different things.
But he said as long as Assad stays in power, it is very difficult to get the moderate rebels to focus their attention on the extremists.