FRANKFURT, Germany (AP) — Europe could face a severe natural gas shortage next year and needs to act now to reduce use, the International Energy Agency said in a report Thursday, warning against complacency in an energy crisis triggered by Russia’s war in Ukraine after countries were able to build up storage of the fuel to heat homes and generate electricity this winter.

The IEA said Europe benefited from some Russian gas supplies over the summer and sharply reduced competition from China for scarce shiploads of liquefied natural gas, or LNG, and those factors could be one-offs, the Paris-based organization said. Along with mild weather, that has pushed down natural gas prices from August highs.