"Oral hearings on the transit contract will begin in Stockholm in late November this year," the Naftogaz press service said.
In June 2014, Gazprom switched Ukraine to a prepayment system for gas supplies over its massive gas debt. The same month, Naftogaz appealed to the Arbitration Court in Stockholm, seeking a retroactive revision of its 2009-19 natural gas transit contract with Russia.
In November 2015, Ukraine stopped buying gas from Russia over the gas price dispute, turning to European suppliers of transit gas.
Naftogaz's total claims to Gazprom stand at $26.6 billion, according to the Ukrainian’s company latest data.