Russian-backed rebels massing to attack key Ukrainian towns

Pro-Russian separatists have intensified shelling of government forces on all front lines and appear to be amassing forces for new offensives on the key railway town of Debaltseve and the coastal city of Mariupol, Ukraine's military said on Saturday. Five Ukrainian soldiers have been killed and 26 wounded in fighting in the past 24 hours, spokesman Volodymyr Polyovy told a briefing in Kiev.
The centre of the main regional city of Donetsk echoed on Saturday with the sound of artillery blasts coming from the north and east. "The situation inside the city is tense and we can hear powerful artillery fire but we have no immediate information about casualties and damages," an official of the rebel-controlled city administration said by phone.
Separatist gains against Kiev government forces in eastern Ukraine, particularly a rebel advance on Debaltseve to the north-east of Donetsk, have given impetus to a Franco-German initiative to try to end the Ukrainian crisis. German Chancellor Angela Merkel, who with French President Francois Hollande met Russia's Vladimir Putin in the Kremlin on Friday, said in Munich on Saturday that there was no guarantee that the peace initiative would work.
But she voiced opposition to the West supplying arms to the Ukrainian government to help them to defend themselves against separatists who Kiev says are supported by Russian arms and Russian troops - an opinion which has set her at odds with a strong body of opinion in the United States.
Moscow says there is no proof of armed involvement by Russian forces. More than 5,000 civilians, Ukrainian soldiers and pro-separatist fighters have been killed since a separatist rebellion erupted in Ukraine's eastern territories in April. A peace deal was struck last September in Minsk, Belarus, but the agreed ceasefire was almost immediately violated and attempts to revive it have failed.
Artillery and mortar fire on populated areas of the east including Donetsk itself have taken a toll on civilian lives, while more than 1,500 Ukrainian soldiers have been killed. The present focus on the battlefield is the town of Debaltseve, a vital rail and road junction which lies in a pocket between the two main separatist-controlled regions.