Producers are watching nervously as above-average winter temperatures have caused inventories to build.

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Average winter temperatures in Novosibirsk are around -13 to -21c in the coldest month (January), and up to 25c in summer.

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The region has seen above-average winter temperatures up to this point, so this is the first big cold snap, making it feel much more severe, he said.

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Parts of the world, most notably Eastern Europe, experienced below-average to extreme cold temperatures this winter.

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So far this winter, the region had seen above-average temperatures, he said.

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