Russia's energy giant Gazprom's natural gas flow through Ukraine dropped by 26.4%, according to the firm's spokesman on Saturday.
"Gazprom will deliver 45.9 million cubic meters of natural gas through Ukraine on May 21," Sergey Kupriyanov noted during a press meeting in the capital Moscow.
Gazprom delivered 62.4 million cubic meters of natural gas via Ukraine on Friday.
He stressed that there has been a significant decrease in the demand for natural gas delivery through Ukraine as of Saturday.
Ukraine stopped buying Russian gas from the Sokhranivka natural gas distribution point in the Donbas region on May 11.
Russia was transiting 30% of the gas to Europe via Sokhranivka, which has a daily capacity of around 30 million cubic meters of natural gas.