NJSC Naftogaz Ukrainy has reserved $3.1 billon on special accounts of the National Bank of Ukraine (NBU) to pay for Russian natural gas, Ukrainian Prime Minister Arseniy Yatseniuk has said.

"We've reserved $3.1 billion on the NBU's accounts to buy the gas," he said in an interview with leading Ukrainian TV channels on Friday.

Yatseniuk said that Ukraine needs to buy about 5 billion cubic meters of Russian natural gas to live through the winter.

The next round of gas talks with the participation of the Ukrainian and Russian energy ministers, and European Commissioner Gunther Oettinger is expected in September 2014, he said.

Yatseniuk expressed hope that it would be the final round of the talks.

Gazprom CEO Alexei Miller earlier said that Naftogaz hadn't paid for 11.535 billion cubic meters of gas supplied by Russia late in 2013 and in April-July 2014.