Displaying increasingly erratic behavior, Russian gas giant Gazprom this week suddenly and significantly increased pressure in the Urengoy-Pomary-Uzhgorod pipeline that delivers Russian gas to Europe.  There was no prior notice.

Gas Transmission System Operator of Ukraine (GTSOU) warned Tuesday of potential damage to one of the transit routes for the gas after reportedly detecting an unannounced change in pressure by Gazprom PJSC.

GTSOU said "Failing to inform the operator in a timely manner carries potential risks to the normal operation of the pipeline," it said without making it clear whether such operations were currently at risk.

Such pressure spikes could lead to emergencies including pipeline ruptures, and pipeline operators are obliged to inform each other about them in advance, the Ukrainian company said.  “Such uncoordinated actions of Gazprom cause concern,” Sergiy Makogon, GTSOU CEO, said. He noted there are existing agreements between the operators that stipulate what information should be provided.

The disarray in the European gas market comes after Gazprom said it would further restrict capacity on Nord Stream 1 (NS1) to 20 percent of capacity. Gazprom justified this by citing maintenance on turbine engines.

Germany's goal of filling gas storage levels to 95% by November is now in doubt without additional measures.