BRUSSELS (REUTERS) - Russia is trying to weaken the European Union, EU leaders agreed on Thursday (Oct 20), noting that they needed to stay the course and remain united in policies towards Moscow.

"Leaders emphasised all sorts of Russian hostilities from airspace violations to information campaigns, cyber attacks, interference into the political processes in the EU and beyond,"the chairman of the EU summit Donald Tusk told a news conference. "Given these examples, it is clear that Russia's strategy is to weaken the EU," he said.

"Creating tensions with Russia is not our aim. We are simply reacting to steps taken by Russia. Of course the EU is always ready to engage in dialogue but we will not compromise our values or principles," he said.

"That is why we agreed to stay the course and above all to keep the unity of the EU."

EU leaders also agreed to consider all available options if Russian military continued to commit atrocities in Syria alongside the Syrian army.

But the leaders stopped short of spelling out in their conclusions that these options included new sanctions against individuals and entities, as in the initial draft of the conclusions.