MOSCOW, December 12. /TASS/. Naftogaz of Ukraine is not ready to buy Russian gas on a prepaid basis without amending the contract, Russian Energy Minister Alexander Novak said in an interview with NTV.

"In the negotiation process we have faced the situation, where Naftogaz is not ready to pay for gas on a prepaid basis without making any changes in the contract," he said.

Novak added that on Friday after the Russia-EU-Ukraine trilateral meeting held in Brussels said on Friday after the Russia-EU-Ukraine trilateral meeting held in Brussels that Ukraine is ready to buy from 1.5 to 4 bln of Russian gas in winter season.

He added that in case Ukraine refuses to buy Russian gas serious risks might occur for gas transit to Europe.

"We see the risks, Naftogaz has injected less gas into underground storage facilities than is required to pass the winter. In addition, the winter will be colder. This means that underground storage facilities reserves will decline faster," Novak said.

Thus, according to the Minister, Naftogaz needs to purchase gas to take less from facilities. "Now you cannot inject additional gas into underground storage facilities. In order to secure safe transit to European consumers and passage of winter it is definitely necessary," he added.

Last year, Ukraine’s cabinet prohibited importing gas by Naftogaz from the Russian Federation. Earlier Gazprom suspended gas supplies to Ukraine until new payment are received.

Russian gas holding Gazprom is ready to supply gas to Ukraine in required volume within the contract framework, the Minister added.