The Druzhba oil pipeline between Russia and Hungary is pictured on May 18, 2022. (Photo: Reuters/VNA)

According to Gazprom, exports to countries outside the region totalled 61 billion cubic metres, a 27.6% fall from the same period last year.

Gazprom said that gas deliveries to China via the "Power of Siberia" pipeline were increasing, but it did not provide any figures.

Since Russia began “special military operations” in Ukraine in February, Moscow has demanded that clients in unfriendly countries, such as EU members, pay for their gas in rubles.

The new requirement is seen as a measure to sidestep Western financial sanctions on Russia's central bank.

So far Poland, Bulgaria, Finland, and the Netherlands have had their natural gas deliveries suspended over refusing to pay in rubles.