Naftogaz Ukrainy only plans to pay Gazprom for the natural gas it orders and receives and not for the gas volumes that Gazprom claims to supply to the territory outside Kyiv's control in Donetsk and Luhansk regions, which may be used to write off losses, Naftogaz has said.

"Gazprom has billed Ukraine for supply of 1.2 billion cubic meters of gas in the first half of the year. Apparently, the Gazprom management has found the ideal method for writing off losses. After all, any figure for supplies can be written in, if the accepting side has no control over it," Naftogaz said on its Facebook blog.

"Naftogaz will not pay for gas that we did not order and have not received," it said.

Gazprom CEO Alexei Miller said on June 30 that gas worth $718.5 million had been supplied to the Luhansk and Donetsk People's Republics (LPR and DPR). Miller continues to refer to that amount as the "Naftogaz debt," while the Ukrainian side maintains just as categorically that the supplies to those territories are illegal.

Moreover, Naftogaz has repeatedly said that it is not accepting gas under the contract with Gazprom at the Prokhorivka and Platove gas metering stations.

"All the reciprocal claims arising in economic relations between Naftogaz and Gazprom must be resolved through arbitration," Naftogaz said.

Naftogaz notes that in recent years, gas purchases from Gazprom are transacted exclusively on a pre-payment basis. In addition, Naftogaz has not paid for or purchased any gas from Gazprom since November 2015. Before that, it only imported gas at metering stations in the territory controlled by Ukraine.