The European Council has called on Russia to immediately withdraw its military assets and forces from Ukraine.

"[The European Council] calls upon the Russian Federation to immediately withdraw all its military assets and forces from Ukraine," the European Council said in the conclusions adopted after an extraordinary meeting in Brussels on August 31.

The document also notes that the European Council remains "extremely concerned by the ongoing and increasingly intense fighting in eastern Ukraine and continues to strongly condemn the illegal annexation of Crimea."

The European Council condemned the increasing inflows of fighters and weapons from Russian into eastern Ukraine, as well as the aggression by Russian armed forces on Ukrainian soil.

"The European Union reiterates the urgent need for a sustainable political solution based on respect for Ukraine's sovereignty, territorial integrity, unity and independence," read the conclusions.