That ruling, made by the Stockholm arbitration court in February, was meant to conclude a legal battle over gas deliveries. But Naftogaz says Gazprom has not complied with the ruling, which obliged the Russian company to resume gas supplies to Ukraine at market equivalent prices and pay $2.6 billion.
Naftogaz said last month it would go to court to seize Gazprom assets in Europe, but would not touch Russian gas transit through Ukraine.
Last week, the Ukrainian firm said it had also asked Swiss courts to enforce the arbitration award and Swiss authorities have taken measures against Gazprom’s assets too.
The legal battle has run alongside Ukraine’s broader political stand-off with Russia.
Gazprom appealed against the Stockholm ruling in April, and the case is ongoing.
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