Ukraine says a convoy carrying aid from Russia will not be allowed to enter the country.
On Facebook, Ukrainian interior minister Arsen Avakov has denounced the 262-truck convoy as provocation by a cynical aggressor.
Interior Minister Arsen Avakov. Photo: AFP
Mr Avakov said they will not be allowed to enter the Kharkiv region of north-eastern Ukraine.
The tucks, said to be carrying nearly 2000 tonnes of aid including grain, baby food and medicine, are expected to arrive at the Ukraine border later on Wednesday.
At least 1500 have died since mid-April, when Ukraine sent troops against pro-Russia rebels in Donetsk and Luhansk regions, the BBC reports.
The fighting has displaced almost 300,000 people, many of whom have fled to Russia.
Meanwhile, Russian President Vladimir Putin is expected in Crimea on Wednesday for a meeting with members of the Security Council.
Russia annexed Crimea from Ukraine in March - a move which triggered the first round of Western sanctions against Moscow.
The trucks left the Moscow area bound for Luhansk on Tuesday morning, according to Russian media and officials.
