The natural gas market was searching for clarity on Wednesday about how Russia’s decision to cut off natural gas supplies to Bulgaria and Poland could impact larger buyers in Europe if they don’t fully comply with the Kremlin’s demands to change how they pay for imports.

Gazprom PJSC confirmed Wednesday that it had stopped delivering natural gas to both countries for their failure to comply with a complex order that requires them to pay in euros or dollars that are then converted by a Russian bank into rubles.

European natural gas prices surged by 25% to an intraday high of about $40/MMBtu as the market baked in the risk of further supply disruptions across the continent. 

“Poland and Bulgaria together losing access to Russian gas has not had a big impact on the total...