Ukraine's national oil and gas company Naftogaz Ukrainy temporarily stopped buying Russian gas on April 1, but the company is ready to resume purchases if documents are signed with Russia's Gazprom giving legal confirmation that the price will fall to about $250 per 1,000 cubic meters, Ukrainian Energy and Coal Industry Minister Vladimir Demchyshyn said.

"We haven't yet taken any [Russian gas] today. If we confirm the price at $250, then we'll buy," he said at a press conference in Kyiv on Wednesday.

Demchyshyn added that Naftogaz and Gazprom carry out bilateral operational activities daily and exchange various documents. He also said that payment and shipments would resume as soon as the companies "agree on a technical agreement that confirms the price before the 'big agreement' is signed."

At the same time, Demchyshyn said he hoped that the terms of Russian gas purchases until the end of the upcoming 2015-2016 heating season would be agreed upon at trilateral talks between Russia, Ukraine and the EU on April 13 and 14.

"We need to prepare for the next heating season. We don't need an agreement for the second quarter; instead we need to extend the memorandum [signed in Brussels in late October 2014] for the next heating season. It's important for us to understand how prices are formed until the end of the 2016 heating season," he said.

"A legal document will be signed on April 13-14 that will adjust the entire period entirely," Demchyshyn added.