Hungary would be in breach of the sanctions regime on Russia if it pays for Russian energy in rubles, European Commission President Ursula von der Leyen told CNN on Friday.

Hungarian Prime Minister Viktor Orban had said Wednesday his country had no problem paying for Russian energy in rubles.

"What Putin is suggesting - this transforming [of] euros into rubles and then paying the gas bill - it would be a breach of sanctions. If you do that, pay in rubles, you breach the sanctions; you circumvent the sanctions we put on Russia," von der Leyen said. 

The Russian ruble had fallen to unprecedented levels following US sanctions on Russia, though it gained ground after President Vladimir Putin had announced that his country would only accept payments in rubles for gas deliveries to "unfriendly countries" in a nod to all EU members in light of the harsh round of sanctions they imposed on Moscow.

According to the European official, Hungary was currently in line with the sanctions regime. She also claimed the EU had never been more united than now, and no country wanted to be the first to break this solidarity, in what seemed like a threat to Budapest.

Despite von der Leyen's assertions, some EU states are examining the Russian proposal of payments in rubles. Slovakia, for one, permitted the possibility of making payments for gas in the national Russian currency, and Hungary is already discussing the issue with Gazprom.

Russia supplies Europe with about 40% of its gas, and the old continent is so highly dependent on Russian energy that many EU member states have gone against calls and pressures calling for a total ban on the import of Russian gas.

Russian President Vladimir Putin said on March 23 that Russia was transferring payments for gas supplies into rubles for "unfriendly countries." He instructed the Russian Central Bank and the cabinet to determine the procedure for transactions with Europe in rubles.

EU imposes 5th tranche of sanctions on Russia

The European Union on Friday published in the Official Journal the fifth package of sanctions on Russia over the war in Ukraine.

Restrictive measures came into force immediately after publication in the Official Journal of the European Union. 

Individuals on the list, which include Sberbank CEO Herman Gref and businessmen Oleg Deripaska, Boris, and Igor Rotenberg, are prohibited from traveling to the EU, and Brussels froze all their assets in the bloc.

In total, the list of new personal sanctions includes 217 individuals and 18 organizations.

The sanctions the EU is imposing on Russia are over its special military operation in Ukraine, launched due to NATO's eastward expansion and the Ukrainian shelling of Donbass, in addition to Moscow wanting to denazify and demilitarize Ukraine.

In response, the US and its allies rolled out comprehensive sanctions, including restrictions on the Russian central bank, export control measures, SWIFT cutoff for select banks, and closure of airspace to all Russian flights. Many of their companies have suspended their Russian operations.