Ukraine forces 'repel rebels in Donetsk airport
Ukrainian government troops say they have repelled an attack by pro-Russian rebels on Donetsk airport.
All morning gunfire was heard from the area yesterday, controlled by government forces despite rebel victories in the rest of the eastern city.
Correspondents say the fresh violence is a big challenge to a fragile ceasefire agreed on 5 September.
Meanwhile Ukrainian Prime Minister Arseniy Yatsenyuk has accused Russia of wanting to "eliminate" his country.
He said Ukraine was "in a stage of war", with the "key aggressor" being Russia.
Yatsenyuk said the goal of Russian President Vladimir Putin "is to take the entire Ukraine", adding that Nato was the "only vehicle" that could protect his country.
Ukraine and Western countries accuse Russia of intervening on the side of pro-Russian rebels in eastern Ukraine. Russia denies this.
Russia's Foreign Minister Sergei Lavrov yesterday described as "nonsense" reports that Russia was intent on creating a buffer zone in eastern Ukraine.
Russia, he said, wanted Ukraine to be a "prosperous, neutral and friendly country".
And he accused the US of "trying to use the crisis in Ukraine to break economic ties between the EU and Russia and force Europe to buy US gas at much higher prices".
The BBC's Paul Adams, in Donetsk, says most of the gunfire around the airport sounded like artillery, but that multiple rocket launchers have also been in use.
On Friday night, he also heard a volley fired from somewhere much closer to the centre of the city.
There are additional reports of plumes of black smoke rising above the airport.
A couple of hundred Ukrainian army troops have been holed up at the airport since June - but our correspondent says that something more concerted now appears to be going on there.
Yatsenyuk's comments come after the US government imposed new sanctions on major Russian banks, defence and energy companies.
The sanctions, announced on Friday, mean that US citizens will not be able to provide loans lasting longer than 30 days to Sberbank, Russia's biggest bank.
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