US says satellite images show deployment of heavy Russian artillery, tanks in east Ukraine

The United States government has reportedly released satellite images that it said showed deployment of heavy Russian artillery and tanks near a "strategic village" in eastern Ukraine.

Geoff Pyatt, the U.S. Ambassador to Ukraine, said on Twitter, "We are confident these are Russian military, not separatist, systems," reported ABC News.

While noting that those systems included surface to air missiles, artillery, and rockets, Pyatt claimed that the separatist groups now had "larger fighting force with more tanks armored vehicles, heavy artillery and rocket systems" than some Nato and European countries.

He also accused Russian military units "along the border" of preparing large shipment of supplies to the pro-Russia rebels in east Ukraine.

The accusation comes as a new ceasefire agreement, agreed in Minsk following four-way talks between France, Germany, Russia and Ukraine, took effect at midnight on Saturday.

The images, taken by the commercial satellite image company DigitalGlobe and tweeted out by Pyatt, are of an area near the village of Debaltseve, which has seen fierce clashes in recent days as both sides fought for control over its railway infrastructure.

Russia has consistently denied backing pro-Russia separatists in Ukraine.