Ukrainian Prime Minister Yatseniuk doesn't rule out that the fact that Russia's humanitarian convoy has crossed the border into Ukraine is a provocation to be used for subsequent accusations of Kyiv of an attack on the convoy.

"Now they anticipate a few vehicles of this so-called humanitarian convoy will just be bombed, probably by Russians themselves, with the aim of raising a clamor around the globe:" It's the junta, which is fighting against its own people," Yatseniuk said in an interview with leading Ukrainian TV channels on Friday.

Ukraine won't let it happen, he said.

Yatseniuk says it's solely Russia's responsibility to ensure the safety of the column.

"That's why we've made it clear: after Russia has violated all international treaties and refused to cooperate with the Red Cross, the entire responsibility lies with the Russian Federation and the Russian president personally," the prime minister said.

As of Friday morning, the Ukrainian side had examined a mere 34 KamAZ trucks, he said, and one of the vehicles, which can carry up to 25 tonnes, had "as much as 800 kilograms of tea."

Other trucks were loaded up to eight tonnes, with the maximum possible 25 tonnes, "that is, they are almost empty," Yatseniuk said.

He said he believes that the situation around the Russian humanitarian convoy is intended to divert attention from the investigation into the crash of Malaysia Airlines MH17 on July 17 in Donetsk region.