Fears over 'fragile' ceasefire
Intense artillery exchanges between Ukrainian government forces and Russian-backed separatists have persisted around a strategic town in eastern Ukraine - fighting that threatens to dash a ceasefire deal brokered by European leaders last week.
Under an agreement negotiated by the leaders of Ukraine, Russia, Germany and France, the warring sides are to begin withdrawing heavy weapons from the front line on Tuesday.
That plan already looks at risk, with the rebels saying they are not satisfied that conditions are in place for the process to go ahead.
Reporters in Luhanske, a government-held town nine miles north-west of the bitterly contested railway hub of Debaltseve, heard sustained shelling on Monday.
Some of the artillery appeared to be outgoing, suggesting it was being fired by Ukrainian troops.
Debaltseve, still in government hands, remains in contention despite the ceasefire. The rebels insist the town should revert to their control because they have encircled it. A loaded Grad rocket launcher was seen pointing in the direction of Debaltseve, but it was not fired while journalists were present.
Observers from the Organisation from Security and Cooperation in Europe, who are supposed to monitor the ceasefire, said separatists had denied them access to Debaltseve.
Despite the ceasefire coming into effect early on Sunday morning, five Ukrainian troops were killed and 25 were wounded in the past 24 hours, Ukrainian military spokesman Andriy Lysenko said.
Separatist military official Eduard Basurin said in a televised news conference on Monday that the government had lobbed artillery at Horlivka, a town under rebel control.
Ukraine, however, blamed that attack on the rebels. The government-appointed police chief of the Donetsk region, Vyacheslav Abroskin, said the separatists shelled the town in order to derail the truce.
The ceasefire appeared to hold elsewhere. The city hall of the rebel capital Donetsk, which came under heavy artillery fire in the past week, said there was no fighting in the area.
Ukraine and the west have accused Russia of arming and supplying manpower to the separatists and have imposed a range of economic sanctions to pressure Moscow into changing its course.
Russia denies all suggestions it is directly involved in the war in Ukraine but the sheer amount of heavy weapons the rebels have access to belies that claim.
The ceasefire had raised cautious hopes for an end to the 10-month-old conflict, which has already claimed more than 5,300 lives.
But Ukraine and rebel officials have already traded multiple accusations of attacks since then.
Both the separatists and the Ukrainian government insist they are committed to the ceasefire negotiated in marathon talks last week. But the Russian news agency Interfax quoted Mr Basurin as saying Monday that conditions are not yet ready to pull back heavy weapons on Tuesday.
"We will begin pulling back equipment from the line of contact if we receive a certain signal, which is if the Ukrainians also do the same thing," Mr Basurin was quoted as saying.
In Berlin, German chancellor Angela Merkel appealed for the ceasefire to be respected.
"The situation is fragile," she conceded, "(but) that was certainly to be expected with a view to Debaltseve."
German foreign ministry spokeswoman Sawsan Chebli mentioned the possibility of a meeting between the German, French, Russian and Ukrainian foreign ministers this week to discuss "further steps" to implement the ceasefire deal.
President Vladimir Putin's aide Yuri Ushakov told Russian news agencies that the ceasefire is "changing the situation dramatically" and that Moscow looks forward to the heavy weaponry being pulled out from the front line.
Meanwhile, the European Union added 19 more people and nine organisations to its list of sanctioned Russian entities, including two Russian deputy defence ministers, the eastern Ukraine-born Russian crooner Iosif Kobzon, who sang to the rebel leaders in Donetsk last year, and several separatist commanders.
The Russian foreign ministry reacted angrily to the decision, calling it "clumsy" in the context of last week's ceasefire deal. The ministry dismissed the new EU sanctions as "running against common sense" and harming chances "to resolve an internal Ukrainian conflict".