Russian President Vladimir Putin has warned that Ukraine faces a natural-gas cutoff that could leave Europe with shortages while saying Kyiv's suspension of gas supplies to separatist parts of eastern Ukraine "smells of genocide."
Putin said on February 25 that Russia hopes it will not halt the delivery of gas to Ukraine but it depends on Kyiv's "financial discipline."
Russian company Gazprom said it would stop sending gas to Ukraine on February 26 if Kyiv does not make a prepayment for more gas.
But Ukraine's state energy company Naftogaz said earlier this week it had only received about half the gas it has paid for and would not pay for new supplies until it received all the gas it is due.
Gazprom said the missing gas was being sent to rebel-controlled parts of Ukraine's eastern Donetsk and Luhansk regions that were no longer receiving gas from Ukraine.
Gazprom started shipping gas directly to separatist-controlled areas of eastern Ukraine on February 19 after Russian Prime Minister Dmitry Medvedev ordered his Energy Ministry to work out a supply plan as "humanitarian aid."
Those shipments are passing through the Prokhorovka and Platovo gas-metering stations on Russia's border with the Luhansk and Donetsk regions.
Putin said Ukraine's reported failure to provide some areas in those regions with gas amounts to "genocide."
"Imagine these people will be left without gas in winter. Not only that there is famine... It smells of genocide," the Russian leader said.
The European Commission helped broker a deal in October between Moscow and Kyiv that was meant to ensure Ukraine received gas during the winter and that supplies of Russian gas to Europe through Ukraine were not disrupted.
Under that agreement, Ukraine promised to pay off arrears for gas received and to prepay for future gas shipments, while Gazprom agreed to lower the price.
That deal is valid until the end of March.
Gazprom said it is supplying gas to the parts of the Donetsk and Luhansk regions in eastern Ukraine that are controlled by pro-Russian separatists -- since Kyiv stopped supplying them.
Putin said Gazprom is not violating the terms of any agreements.
But in Brussels, EU Energy Commissioner Maros Sefcovic said he has received conflicting information from Moscow and Kyiv on the gas supplies being sent to the rebel-held eastern regions of Ukraine.
"At this stage...we have conflicting approaches how the gas, if supplied to these territories -- which is very difficult to establish for our monitors who are at this time at the dispatch center in Kyiv -- should be billed," he said.
Sefcovic added that he had proposed "to make sure the [existing] winter package agreements are not touched in any way, that everything should work as it has been working...that we would get assurances that the gas transit would work as it has been working until now and that the issue of supply to Donetsk and Luhansk territories and the issue of the cost would be treated separately."
He also said the EU Commission will present the results of its investigation into Gazprom's business practices with EU member states in a "matter of weeks."
The EU Commission launched an investigation into the state-owned energy giant in 2012 on suspicion that it was abusing its market dominance in several eastern EU member states.
Brussels is especially looking into whether Gazprom has hindered the free flow of natural gas across Europe and whether it has imposed excessively high prices by linking the price of its gas to oil.
The decision to present the results of the investigation and to announce possible penalties lies with Sefcovic's colleague, EU Competition Commissioner Margrethe Vestager.
The probe was initially supposed to be presented last year but has proceeded slowly since the Ukraine conflict flared up.
Sefcovic added that he will propose that, in future, the EU Commission take part in negotiations between EU members and suppliers such as Gazprom.
With reporting by Reuters, AFP, TASS, and Interfax