"Gazprom would lodge a counterclaim against Ukraine's Naftogaz with the Stockholm arbitration court," said Gazprom chief Alexei Miller.
The Russian and Ukrainian energy companies have been locked in a fresh energy dispute since Moscow nearly doubled the price Kiev pays for natural gas in the wake of the February ouster of Ukraine's Russian-backed president.
Moscow has threatened to cut gas supplies if Kiev does not pay its debt in full, but has offered to reduce the price demanded by 20 per cent to USD 385 per 1,000 cubic metres.
Miller today accused the Ukrainian company of intransigence and unwillingness to come to a compromise.
"From the very beginning of the talks the Ukrainian side has never sought any compromise, never sought any agreements," Miller said, adding that Ukraine chose to speak with Russia from a "position of ultimatums."
Miller said such a stance was "strange (and) absurd."
"It's simply blackmail," he said in televised remarks.
"It looks like the goal of the Ukrainian side is to aggravate to the maximum our relations in the gas sphere."
Russia has repeatedly pushed back the deadline for Ukraine to pay for Russian energy deliveries after cash-strapped Ukraine made an initial payment of USD 786 million.
Miller reiterated today that Naftogaz had now until early Monday to pay Gazprom USD 1.95 billion.
"This deadline will not be pushed back any more," Miller said.
Moscow says Kiev owes it $4.5 billion in outstanding bills.
Russian President Vladimir Putin has warned that European energy supplies may be interrupted if Gazprom is forced to pull the plug on Ukrainian gas deliveries and called on the West to help Kiev settle its bills.
About 15 per cent of the natural gas that Europe consumes is Russian gas that transits through Ukraine.