It said shipments of gas may be halted if payment for June deliveries does not arrive by the deadline. Gazprom chief Alexei Miller noted the decision and the deadline were because of outstanding debt on Ukraine's part. Otherwise, "Ukraine will receive zero cubic meters (of gas) in June," the Russian news agency Interfax reported.
Prime Minister Dmitry Medvedev recently said on Russian television it could no longer be a "nanny" for Ukraine.
Miller added Ukraine could dip into an International Monetary Fund aid package of $17 billion to make the payment. "According to our information, Ukraine has received money from the first IMF tranche (transfer)," he said.
Ukraine has refused to pay its obligations as a protest of Gazprom's near-doubling of the price of natural gas. Ukrainian Finance Minister Oleksandr Shlapak said Monday his country was willing to pay its creditor as soon as Russia lowers the price.
Gazprom currently charges Ukraine $485.50 per 1,000 cubic meters of gas, the highest rate of any of its customers in Europe.