Ukrainian servicemen carrying weapons, seized from pro-Russian separatists, near Slovyansk in early July.
The United Nations has not received any hard evidence that Russia supplied pro-Russian separatists in eastern Ukraine with weapons, the United Nations High Commissioner for Human Rights said Thursday.
"We were unable to get hard evidence of the supply of weapons," Pillay said in comments carried by ITAR-Tass.
Washington and Kiev have both claimed they possess proof that Russia had been supporting the Ukrainian insurgency through the provision of military equipment. In the wake of the downing of Malaysia Airlines Flight MH17 on July 17, which claimed 298 lives, these accusations grew to a fever pitch.
Pillay said that both the separatists and Ukrainian troops were at fault for using heavy weaponry against civilians through the course of the ongoing conflict, which the UN estimates has claimed more than 1,000 lives since mid-April.
Referring to the downing of MH17 as an "attack on civilians," Pillay said the use of such weapons as the Buk missile system, which is believed to have been used in the attack, constitutes a violation of international law.
Russia's Defense Ministry has denied claims that Moscow had provided support for the rebels, and hit back against such accusations earlier this month with claims that its satellites had detected a Ukrainian fighter jet near the Malaysia Airlines plane at the time of the incident.
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