Kiev and Moscow have filed lawsuits against each other over the gas price dispute that led to Russia cutting off Ukraine's gas supply this morning.
Russia said it has filed a lawsuit at the Stockholm arbitration court to try to recover Ukraine's $4.5 billion debt for gas.
Meanwhile, Ukrainian state gas company Naftogaz said it filed another lawsuit to try and recover $6 billion in what it said were overpayments to Gazprom.
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