Sikela said on Twitter no outages were appearing in the central European country, while also saying Russian President Vladimir Putin was leading an energy war against Europe.

"Gas supplies to (the Czech Republic) are smooth and not showing any outages," he said, adding built-up gas stores could last without problems until the end of October.

The central European country is nearly 100% dependent for its gas on Russia, and has border transfer stations between it and Germany, as well as Slovakia.

The announced supply capacity cut for Nord Stream 1 to Germany is the second in as many days, and means that the pipeline will run at just 40% capacity.

Germany's economy minister said the move was aimed at sowing uncertainty and pushing up fuel prices.

(Reporting by Jason Hovet)