KIEV, Aug. 18 - Ukraine's pro-Western leadership and Russia traded blame on Tuesday for a sharp escalation in violence that threatened to see all-out warfare return to the former Soviet nation's separatist east, AFP reported.

Russian President Vladimir Putin pinned the upsurge on alleged preparations by Kiev to grab back territories it had lost in the course of the 16-month war.

"Unfortunately, we are now witnessing an escalation whose blame lies not on the rebels but on their foes," Russian news agencies quoted Putin as saying.

"I hope that things will not lead to large-scale violence."

But Ukrainian army spokesman Vladyslav Seleznyov accused "Russia of trying to pile additional pressure on Ukraine."

"This once again proves that the (insurgents) are not looking for a peaceful way out of this conflict," he told reporters in Kiev.

The Ukrainian army on Tuesday reported the death of one serviceman and the injury of another in the Russian-speaking provinces of Luhansk and Donetsk.

Monday's clashes were the culmination of days of restlessness in the former Soviet nation that saw the number of rocket and heavy artillery fire exchanges climb to levels not recorded since the signing of a very loosely observed February armistice.

The militias have been trying to seize a road linking their de facto capital Donetsk with Mariupol, a southeastern port held by the government and responsible for exporting much of the industrial region's factory output.

Mariupol also provides a land bridge between eastern rebel territories and the Crimea peninsula that Russia seized from Ukraine in March 2014.

France said Ukrainian President Petro Poroshenko would travel to Berlin on Monday to discuss the latest spike in violence with German Chancellor Angela Merkel and French President Francois Hollande -- the West's main sponsors of the February accord.

Some analysts in Kiev saw Putin's exclusion from the meeting as a diplomatic snub.

The violence has sparked a new diplomatic flareup between Moscow and Western powers who want to prop up Kiev's new pro-European leaders against what they view as Russian aggression.

"There can be no mistake as to who is responsible -- Russia and the separatists are launching these attacks, just as they escalated the conflict last August," US State
Department spokesman John Kirby told reporters.

He appeared to be referring to Ukraine's loss of hundreds of soldiers who were surrounded by a far more heavily-armed militia unit in the east a year ago.

Russia's foreign ministry denounced Kirby's comments as "the US State Department's effective approval of the Ukrainian army's attacks on rebel positions." (afp/ez)