Ukraine’s natural gas transmission system operator (TSO) warned Tuesday of potential damage to one of the transit routes for moving Russian natural gas to Europe after reportedly detecting an unannounced change in pressure by Gazprom PJSC.

Gazprom map

Gas TSO of Ukraine reported a sharp increase in pressure on the Urengoy-Pomary-Uzhhorod (UPU) pipeline section on the border of Ukraine and Russia. The change came without notice from Gazprom, according to the TSO. CEO Sergiy Makogon said the pressure change could cause major damage unless there is coordination between each party.

“Such uncoordinated actions of Gazprom cause concern,” Makogon said. He noted there are existing agreements between the operators that stipulate what information should be provided. 

“Such a step looks...