On Wednesday, Russian energy giant Gazprom reduced the capacity of Nord Stream 1 pipeline, delivering only a fifth of its total capacity of gas to Europe.
About one-third of all Russian gas exports to Europe goes through Nord Stream 1.
The cut in supplies will make it hard for European nations to meet goals to refill storage and keep their citizens warm during the winter months.
Brussels has accused Russia of using energy as a weapon to blackmail the EU and retaliate for Western sanctions over its invasion of Ukraine.
Moscow has blamed the delayed return of a Siemens serviced turbine used at Nord Stream 1, that underwent servicing in Canada and sanctions for the supply cuts.
