KIEV, Dec. 19 - Naftogaz Ukrayiny, the national energy company, said Gazprom may be preparing for an escalation of tensions and perhaps disruption in gas supplies to Europe during the winter.

Naftogaz made the statement hours after Gazprom CEO Alexei Miller warned Friday that Ukraine may be forced to use Russian gas transit to Europe if air temperature drops significantly.

“Naftogaz considers the allegations as Russia’s preparation for a new gas crisis in January and February 2017,” the Ukrainian company reported in a statement.