Russian gas flows to Europe via Ukraine fell by a quarter on Wednesday after Kyiv halted use of a major transit route blaming interference by occupying Russian forces, the first time exports via Ukraine have been disrupted since the conflict began.
Ukraine has remained a major transit route for Russian gas to Europe even after Moscow launched what it calls a "special military operation". The transit point that has been shut usually handles about 8 per cent of Russian gas flows to Europe.
Kremlin-controlled Gazprom, which has a monopoly on Russian gas exports by pipeline, said it was still shipping gas to Europe via Ukraine, but volumes were seen at 72 million cubic metres (mcm) on Wednesday, down from 95.8 mcm on Tuesday.
GTSOU, which operates Ukraine's gas system, said on Tuesday it would suspend gas flows through the Sokhranivka transit point, which it said delivered almost a third of fuel piped from Russia to Europe via Ukraine.
It said it was declaring "force majeure", a clause invoked when a business is hit by something beyond its control, and would divert deliveries for Europe to another route, the Sudzha entry point, the biggest of Ukraine's two crossing points.
The gas pipeline via the Sokhranivka point runs through Ukraine's Luhansk region, part of which has been under control of pro-Russian separatists. Sudzha lies further north-west.
Gazprom said on Tuesday it was "technologically impossible" to shift all volumes to the Sudzha route, as GTSOU proposed.
Data provided by Gazprom on Wednesday suggested only Sudzha was being used. GTSOU data showed gas transit volumes had declined after nominations for Russian gas via the Sokhranivka entry point for May 11th fell to zero.
Daily nominations for Russian gas deliveries to Slovakia via Ukraine fell on Wednesday, data from Slovakian operator TSO Eustream showed. Nominations via the Velke Kapusany border point were around 717,923 megawatt hours (MWh) per day on Wednesday, versus about 883,844 MWh per day on Tuesday, the data showed.