KIEV, June 13 - Kiev reported the deaths of six soldiers and accused Moscow of abetting an attack on one of its Russian consulates, AFP reported.

The latest fatalities in the twisting and hotly disputed zone separating Ukrainian forces from their pro-Russian foes in the separatist east add to the strains of a February truce designed to end one of Europe's deadliest conflicts in decades.

The 14-month war has claimed nearly 6,500 lives and turned Russian President Vladimir Putin into an increasingly isolated figure blamed for pulling a Cold War-era pall over Moscow's relations with the West.

The February accords that the leaders of Germany and France effectively forced upon Putin and Ukrainian President Petro Poroshenko had initially helped limit the fighting to hotspots whose status had been under dispute from the start.

But last week saw intense mortar and artillery fire return to previously quiet regions, claiming more than 35 lives.

Western monitors said the clashes came after both sides pulled their heaviest guns up to the truce line in apparent preparation for a hot summer campaign.

Saturday's casualties bring to about 50 the number of people reported killed this month -- a figure that fails to include all the deaths suffered by the secretive and partially splintered rebel command.

Ukrainian military spokesman Andriy Lysenko said overnight clashes had been especially heavy around the fragmented remains of the once-gleaming airport on the outskirts of the separatists' de facto capital Donetsk.

"Our enemies have thrown tanks, infantry combat vehicles and artillery into battle," Lysenko said.

A separate Kiev statement said "the past few days have seen the highest rate of activity from pro-Russian (rebels) in a month."

Donetsk insurgents blamed Kiev for shelling the very regions mentioned by Lysenko. They also accused Poroshenko's forces of committing "99 ceasefire violations" since Friday.

The Pentagon, meanwhile, is "poised" to station heavy weapons for up to 5,000 American troops in several Eastern European and Baltic countries to deter Russian aggression, the New York Times reported Saturday.

The proposal, if approved, would be the first time since the end of the Cold War that the US has had heavy military equipment -- including battle tanks -- in newer NATO members that were once under Moscow's influence as part of the Soviet Union. (afp/ez)