Russia should do more to contribute to violence de-escalation in Ukraine where "a democratic transition should be implemented via free elections," leaders of top European countries and the United States said on Friday.

In a communique released by France's president office, the Elysee, Francois Hollande, his American counterpart Barack Obama, German Chancellor Angela Merkel, Italian Prime Minister Matteo Renzi and British Prime Minister David Cameron called on Russia to respect its commitment to ease tensions in Ukraine in line with Geneva accord.

"Russia ... should contribute to the de-escalation by refraining from inflammatory statements or intimidation. Ukraine's territorial integrity and sovereignty must be fully respected," they said in a common statement.

They also urged a swift implementation of Geneva agreement, forged last week, "to allow an exit from the crisis and prevent deterioration of the situation."

In April 17, Russia, Ukraine, the United States and the European Union in Geneva agreed to disarm armed groups including militants who seized buildings in the east region of Ukraine, as part of a plan to restore stability in the country.

As tensions rise again in Ukraine, Hollande, Obama, Merkel, Renzi and Cameron asked their European allies and G7 nations to impose further sanctions against Moscow to guarantee the region's security.

Meanwhile, Russia began drills near the border in response to Ukrainian military operations that left five pro-Moscow protesters dead on Thursday.

Ukraine has been plunged into a chaotic violence since November 2013 following the government's backtrack on European integration which angered many in the west of Ukraine.

It was hit by a fresh wave of unrest after Crimea left Ukraine to join Russia last month.