Ukraine conflict enters 'most deadly period', UN warns

Pro-Russian separatists in eastern Ukraine reject further peace talks and announce offensive on all fronts

Members of the armed forces of the Donetsk People's Republic in the outskirts of Donetsk

The Ukraine conflict has entered its "most deadly period", the United Nations warned on Friday, as Pro-Russian separatists in eastern Ukraine rejected further peace talks and announced an offensive on all fronts.

Alexander Zakharchenko, the head of the self-proclaimed Donetsk People's Republic, said he saw "no point" in further talks with Kiev.

"There will be no more ceasefires and rotation," he said. "There will be no attempts to talk about ceasefire from our side," he said. "Kiev does not understand that we are now able to attack on three fronts at once."

Mr Zakharchenko said the goal of the new offensive was to seize control of the entire territory of Donetsk region, which the rebels claim is their legitimate territory. They currently control about one third of it.

Earlier this week rebel forces inflicted a decisive defeat on Ukrainian troops at Donetsk airport, bringing to an end an eight month siege.

The next targets for the rebel offensive are likely to include Debaltsevo, a strategic railway junction, checkpoints to the north of the city of Luhansk, and the sea port of Mariupol.

The announcement came dispute international calls to return to a ceasefire line agreed at peace talks in Minsk in September.

The United Nations said on Friday that at least 5000 people have been killed in the conflict, including at least 262 in the past nine days, making it the deadliest period of the conflict so far.

Vladimir Putin blamed the Ukrainian government for the increase in violence and criticised Petro Poroshenko, the Ukrainian president, for ignoring his proposals for a peace plan.

"The Kiev authorities have given an official order to start large-scale military operations practically throughout the whole line of contact. The result is tens of killed and wounded, not only among the military on both sides but ... among civilians," Mr Putin told senior state officials in televised comments.

Mr Poroshenko has blamed Russia for the new offensive, saying there are approximately 9000 Russian troops supporting the separatists.

Nato accused Russia of a "substantial increase" in its supply of heavy military equipment to the separatists.

"We speak about tanks, armed vehicles, artillery, advanced air defence systems," Jen Stoltenberg, the Nato secretary general, said during a visit to Kosovo.

Mr Stoltenberg said he was prepared to meet Sergey Lavrov, the Russian foreign minister, in Munich next month.

By Roland Oliphant, Moscow