Russia's Foreign Ministry on Thursday accused Ukraine of trying to "hide the truth" about Ukrainian nationals alleged to have fought alongside Georgian troops against Russia during a brief war in August.
"Ukrainian authorities are trying under different pretexts to hide the truth on the real events in South Ossetia and the involvement of the Ukrainian side," the foreign ministry said in a statement.
Ukraine's SBU intelligence agency on Wednesday called in for questioning Valery Konovalyuk, the head of a parliamentary committee inquiring on the possible involvement of Ukrainians in the war.
Konovalyuk, a lawmaker from the opposition Regions Party, which is broadly favorable to Moscow, was preparing to show journalists a video purporting to reveal the actions of Ukrainian mercenaries in the war.
The SBU accused Konovalyuk, who earlier alleged that around 15 Ukrainian nationals had taken part in the war, of intending to put out "misleading information prepared with the help of Russian security services."
Russia's Foreign Ministry responded saying the video "collected impartial facts and proof of the attack perpetrated by Georgia against South Ossetia, as well as of large deliveries of arms to the Georgian army by Ukraine."
Ukraine has denied that any Ukrainians took part in the Russia-Georgia war.