The move has led UK energy companies that receive supplies from Ukraine, including British Gas owner Centrica, to speculate that the reduction could force British prices up in the coming months.
Talking to the Telegraph, a Centrica spokesman said: "We have no plans to raise bills between now and the end of the year but we are all looking at how winter pricing turns out. This potentially adds to upward pressure."
News of possible price hikes has come after Ofgem revealed gas customers may face small increases on their energy costs as it plans major investment into the replacement of old mains pipes.
The UK energy regulator has told consumers to expect an increase of £1 per year in real terms on their bills.
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