Four European gas buyers have already paid for gas deliveries from Russia, complying with the Kremlin's resolution to only accept rubles in exchange for Russian gas, a person close to the Russian Gazprom said on Wednesday.

Other buyers rejecting Moscow's term would not mean Russia cutting gas off more European countries after its halt Wednesday of gas flows to Poland and Bulgaria, as it is likely that further cutoffs would not happen until the second half of May when the next round of payments is due, the same source said, speaking on to Bloomberg on condition of anonymity.

Ten European firms had already opened the accounts at Gazprombank needed to meet Russia's payment demands, the source added after Russian energy giant Gazprom announced on Wednesday that it had completely suspended gas supplies to Bulgaria's largest natural gas distribution company Bulgargaz and Polish oil and gas company PGNiG, due to their failure to pay for gas in rubles.

Moscow had asked the West for rubles in return for its gas supplies starting April 1 after the European Union imposed sanctions on Russia over the war in Ukraine. The 27-nation bloc told member states the mechanism the Kremlin proposed required opening euro and ruble accounts with state-controlled Gazprombank, which would be in violation of the sanctions imposed on the country.

European stock markets and oil prices surged on Wednesday after enduring heavy losses against the US dollar amid widespread economic unrest, though the euro fell down to its lowest rate against the USD since April 2017.

Russia had notified the West that it needed them to pay for gas deliveries in rubles, with Kremlin spokesperson Dmitry Peskov saying his country would not deliver gas to Europe for free, in a reiteration of President Vladimir Putin's that Russia would not accept anything but rubles for gas deliveries to "unfriendly countries."

The list of unfriendly countries includes the US, Canada, the EU, the UK, Montenegro, Switzerland, Albania, Andorra, Iceland, Liechtenstein, Monaco, Norway, San Marino, North Macedonia, and also Japan, South Korea, Australia, Micronesia, New Zealand, Singapore, and Taiwan.

However, Bulgaria later joined the West in its bid to sanction Russia over the war in Ukraine, expelling more Russian diplomats on suspicion of "spying", just two weeks after declaring 10 Russian diplomats "personae non grata."

The Kremlin also explained on Wednesday that the suspension of natural gas shipments to Poland and Bulgaria was due to their reluctance to pay in rubles and the outcome of hostile acts toward Russia.