Slovak state gas importer SPP has paid a bill for Russian natural gas in euros and has also opened a rouble account with Gazprombank, the company said on Friday, in effect accepting a payment scheme demanded by Moscow.

The European Union's executive told member states this week they can keep buying Russian gas without breaching sanctions imposed on Russia over its invasion of Ukraine.

Payments for Russian gas have become an issue since Moscow demanded that foreign buyers start paying in roubles, and Russia cut supplies to Poland and Bulgaria for refusing to do so. On Saturday, Russia is set to cut off supply to Finland.

"We have paid in euros our commitment toward Gazprom," Prokypcak said in an interview on Slovak public television RTVS, which said that the payment was made on May 17, meeting a May 20 deadline.

"It is in euros also because the bill itself was issued in euros by Gazprom. Following that, the money was sent to a Gazprom account and I have confirmation that the payment has been received," Prokypcak said.

"Monetary conversion is underway that will be concluded by handing roubles to Gazprom, and following that, natural gas supplies continue," he added.

While the European Commission advised companies against opening rouble bank accounts at Gazprombank, as requested by the Kremlin, it has not explicitly said doing so would breach sanctions in its formal written guidance.

Slovak Economy Minister Richard Sulik ordered the payment based on the Commission stance, the ministry said.

"There was no breach of any contract, there was no amendment attached," it said.

Prokypcak said that the conversion into roubles was outside SPP control.

"For us really the important moment of fulfilling our commitment is the euro payment," Prokypcak said.

A spokesman for SPP told Reuters that the company paid in euros but the payment was converted to its rouble account before continuing to Gazprom.

"(A rouble account) is needed because Gazprom will not accept payment in euros, so from one (account) to another of ours, euros must be converted to roubles," Ondrej Sebesta said.

"We say we paid in euros and the Russians will say we paid in roubles," he said.

Asked if SPP was using the payment scheme demanded by Russia, he said: "Yes, same as everyone else."

Gazprom did not immediately reply to a request for a comment.

Russian Deputy Prime Minister Alexander Novak said on Thursday that half of Gazprom clients have opened accounts at Gazprombank.

SPP is the main Slovak gas importer, supplying 36 TWh last year, accounting for around 60% of the domestic market. It takes the vast majority of its gas supply from Russia.

(Reporting by Jan Lopatka and Robert Muller in Prague; Editing by Jason Neely, Alexander Smith and Louise Heavens)