Russia's energy minister says his country has a "take or pay" deal for natural gas with Ukraine that, in the absence of any fresh agreement, comes into effect on April 1.
Aleksandr Novak told journalists the "take or pay" clause was part of the 2009 gas agreement with Ukraine, obligating Ukraine to pay for gas it contracted for whether it uses it or not.
Novak added that since there was no new agreement with Ukraine for gas supplies, the 2009 deal "continues to be in effect."
Novak said that did not change Russia's demand that Ukraine pay in advance for gas supplies.
Ukrainian Energy Minister Volodymyr Demchyshyn said earlier on April 1 that Ukraine was not currently buying gas from Russia's Gazprom and would only resume purchasing it if a price of $250 per 1,000 cubic meters was agreed to.
Novak indicated that price might be acceptable.
He said the gas price for Ukraine in the second quarter of 2015 was set at $348 per 1,000 cubic meters but added that the price could be subject to a discount of $100, bringing the price for gas to Ukraine down to $248.
Gazprom has said Ukraine paid $329 per 1,000 cubic meters in the first quarter of the year -- the final period covered by an EU-brokered deal reached in October.
That agreement restored supplies to Ukraine after a monthslong hiatus, easing fears that severe tensions between Kyiv and Moscow over Russia's takeover of Crimea and support for rebels in a war in eastern Ukraine would affect supplies of Russian gas to Europe via the transit country.
Former Ukrainian President Viktor Yanukovych reached a deal with Russia to purchase gas for $285 per 1,000 cubic meters.
But after the pro-Moscow Yanukovych was ousted in late February 2014, Russia demanded $485 and full payment of Ukraine's multibillion-dollar debt for gas supplies already received.
That prompted the European Union to mediate gas negotiations between Russia and Ukraine.