The Nord Stream gas pipeline linking Russia to Germany restarted on Thursday after 10 days of maintenance work, its operator told AFP.
"It's working," a Nord Stream spokesman said, without specifying the amount of gas being delivered. The German government had feared the pipeline would not be reopened by Moscow after the scheduled work.
According to data given by Russia's state-owned energy giant Gazprom to Gascade, the German operator of the line, 530 GWh would be delivered during the day.
This was only 30 per cent of its capacity, Klaus Mueller, president of Germany's energy regulator, the Federal Network Agency, said on Twitter.
Gazprom has cut flows to Germany via the vital Nord Stream 1 pipeline by some 60 per cent in recent weeks, blaming the absence of a Siemens gas turbine that was undergoing repairs in Canada.
The German government has rejected Gazprom's turbine explanation and believes Russia is squeezing supplies in retaliation for Western sanctions on Moscow over its invasion of Ukraine.
The Nord Stream 1 pipeline under the Baltic Sea has been shut down since July 11 to undergo annual maintenance.