Lithuania's government says it will file a €1.45 billion ($1.9 billion) claim against Russia's Gazprom, alleging that the world's largest natural gas company has hiked prices unfairly.

Government ministers said Wednesday the size of the claim covers what the country has overpaid for natural gas since 2004, when Gazprom obtained a major stake in Lietuvos Dujos, the country's largest gas importer, and changed the formula for determining the gas price.

Lithuania imports all its natural gas from Russia and has become more dependent on its eastern neighbor after closing a Soviet-era nuclear power plant in 2009.

Gazprom is poised to lose influence over gas policy in the Baltic state after a law on deregulation, passed earlier this year, goes into effect in 2014.

Lithuania's claim will be submitted to a Swedish arbitration court.