Russia slashed nearly half its natural gas exports to Poland earlier this week amid soaring tensions over Ukraine, Poland’s state gas firm is claiming. The shortfall forced Poland to halt gas deliveries to Ukraine through “reverse-flow” pipelines, which some analysts say was Russia’s original goal, according to media reports.

Warsaw-based PGNig SA (WSE:PGN) said Russian gas volumes have dropped by 45 percent, BBC News reported Thursday. Moscow and Kiev are in a gas pricing dispute, and in June, Russia’s state-owned OAO Gazprom (MCX:GAZP) stopped gas supplies to Ukraine. Poland, Hungary and Slovakia have since pumped some of their own gas supplies into Ukraine.

Gazprom denied Poland’s allegations that it reduced gas supplies. “Currently exactly the same volume of gas is being delivered to Poland as on previous days,” the gas monopoly said in a Wednesday statement cited by Russia’s Ria Novosti news agency. Hungary and Slovakia have not yet reported significant drops in their own supplies from Russia, the BBC noted.

Europe gets about one-third of its gas supplies from Russia, roughly half of which is piped through Ukraine.

If Russia is reducing gas supplies, it could be punishing Poland for undermining Moscow’s strategy, analysts told BBC. Russian President Vladimir Putin has previously warned of consequences if EU member states sent reverse-flow deliveries to Ukraine.

Ihor Prokopiv, chief executive of Ukraine’s gas pipeline operator Ukrtransgaz, made similar accusations against Moscow. “Russia started limiting gas supplies to Poland in order to disrupt the reverse [flows] from Poland that we receive,” he told Russian reporters, The Guardian noted.

Other Gazprom sources, who acknowledged the shortfall, said it could be the result of maintenance work in gas fields and along pipelines ahead of the winter season, when gas demand is highest, the Guardian noted. Jonathan Stern, a member of the EU-Russia Gas Advisory Council, reasoned that if Gazprom actually wanted to punish Poland, it would wait until the colder months when a gas shortfall would be more severely felt. “The Russians are acutely aware that any moves at this time will be interpreted in the worst possible light,” Stern told the Guardian.

Last week, Europe’s energy chief said he is not ruling out Russia’s blocking natural gas flows to the rest of Europe in retaliation for Western sanctions over the Ukraine conflict. European Energy Commissioner Guenther Oettinger addressed what he called the “worst-case scenarios” for the region’s energy security this winter as tensions with Moscow escalate.