Ukraine has not paid off any of its debt to Gazprom despite a deadline for the nation to start reducing its debt by midnight (Moscow time) on Monday.
A Gazprom spokesperson told Reuters: “There have been zero payments from Ukraine.”
Ukraine owes Gazprom $2.2bn (£1.3bn) for supplies of natural gas.
Gazprom did not say what action it would take if Ukraine failed to pay. The nation has missed previous deadlines without punishment.
However, in recent years disputes over the price of gas have seen Gazprom cut off supplies to Ukraine.
That happened during the winters of 2005 and 2008.
