Europe is staring down another nasty winter of high natural-gas prices. This time, the problem isn't Russia, but the Strait of Hormuz.

Futures prices for natural gas on the continent reached their highest level since early 2023 in recent days, as traders bet the waterway could stay closed into winter.

Only a handful of liquefied natural gas cargoes have made it through Hormuz this month, according to Helge André Martinsen, energy analyst at DNB Carnegie in Norway. Before the war, around a fifth of the world's LNG came through Hormuz, mostly from Qatar.

Europe got much less of its gas from Qatar than from the U.S. But low supplies of LNG from the Middle East mean more competition for what's left, spurring a bidding war between European and Asian buyers.

Europe burns natural gas to heat homes, generate electricity and fuel factories. It builds stockpiles during the summer to use in the winter. But it has struggled to refill its gas stores in recent months, as Asia has bid high prices to make up for its own shortfall of Qatari gas, according to Argus Media analyst Natasha Fielding.

For the moment, prices are still far below their highs from 2022, when supplies from Russia dried up after the invasion of Ukraine.