The unfolding crisis in Ukraine, which is locked in dispute with gas giant Gazprom over a bill due Monday morning, is of "utmost importance" to the world's natural gas market, according to the head of global body the International Gas Union.
Jerome Ferrier, president of the IGU and an executive of French power company Total, told CNBC he is "optimistic on the current situation," despite Ukraine's refusal so far to pay a $2.2 billion bill due Monday morning.
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Russia has hiked gas prices for Ukraine from $268 to $500 per cubic meter since the dispute over its annexation of the Crimea region of Ukraine erupted. Gazprom has threatened to claw back discounts made on gas already paid for, which has helped fuel the current stand-off over payment.