Nauseda said the current challenges required unity and cohesion from the EU, NATO and Eastern Partnership countries, adding that the EU would not tolerate aggression and threats to the sovereignty and territorial integrity of its eastern neighborhood.

"We are very realistic about the situation on the Ukrainian border," the president told journalists. "We see a clear effort to destabilize the security situation there and across the region. We need to prevent such processes".

"That is why the European Council was able to unanimously decide that, in the event of such an escalation of the conflict, we are prepared to introduce additional restrictive measures to counter Russia's aggressive actions towards Ukraine," he said.

Nauseda also said that Ukraine could continue to count on full support on its reform path.

At their summit in Brussels on Thursday, EU leaders also discussed the fight against the COVID-19 pandemic, migration issues, the bloc's relations with China, and the situation in Belarus.