Ukraine's government said Russia's refusal to amend its natural gas contracts is putting European supplies at risk, RIA Novosti reports on its Web site Tuesday.
"Russia's possible refusal to develop the gas contracts is a serious threat to [national energy firm] Naftogaz's operations and consequently the uninterrupted transit of Russian natural gas via Ukraine," Bohdan Sokolovskiy, energy security adviser to Ukraine's president, is quoted as saying.
A new gas pricing row broke out between the two countries Monday, with reports Ukraine plans to raise the tariff for transit of Russian gas through its territory by 50%-80% in 2010.
Russian President Dmitry Medvedev deemed this unacceptable and told gas giant OAO Gazprom (GAZP.RS) not to pay.