WARSAW (Reuters) -Poland's biggest energy company Orlen warned gas companies in Hungary, Slovakia and Austria that it could seize their payments for imports from Russia's Gazprom, sources familiar with the matter said.

The warnings, in letters sent over a month ago, are linked to claims for losses Poland incurred after being cut off from Russian supplies in 2022, two sources with knowledge of the letters told Reuters. 

Poland was cut off for not paying in roubles as Western nations imposed sanctions on Russia following its invasion of Ukraine.

The warnings from Orlen spurred Budapest to issue a decree in May, one source said, with the aim of preventing payments by state-owned energy conglomerate MVM CEEnergy to Gazprom from being seized, arguing it would put Hungary's energy supply at risk.

The European gas market has faced uncertainty over supplies from Russia after Austria's OMV warned last month of the suspension of supplies from Russia's Gazprom following a foreign court ruling, without identifying the case.

Orlen said it remains in a dispute with Gazprom regarding a long-term gas contract.

"Due to legal interest, the company does not comment on ongoing arbitration proceedings or legal actions taken," Orlen said in response to a question from Reuters. OMV declined to comment on the matter.

Slovakia's SPP, which buys gas from Gazprom said on Wednesday that a recent legal change protects it from any potential seizure of its Russian gas imports or related claims.

Last year, Poland's Europol Gaz filed a $1.45 billion claim against Gazprom for overdue payments and lost revenue from gas transmission services after 2022. Orlen is the sole owner of Europol Gaz, which operates the Polish section of the Yamal gas pipeline linking Russia and Europe.

In 2022, Poland terminated its agreement with Russia to receive Russian gas via the Yamal pipeline. Warsaw earlier rejected a demand to pay for the fuel in roubles and Moscow responded by cutting off supplies.

The development shows a further split inside the European Union over the halt of Russian energy supplies, which have led to tariffs disputes and a decline in industrial productivity.

Details of the Polish ruling were not available and the court was unable to immediately supply the details.

Orlen is claiming over $350 million from MVM CEEnergy as security for what it is owed by Gazprom, a source said, citing a ruling in a Warsaw court.

MVM CEEnergy did not respond to requests for comment.

German utility Uniper earlier this month won a multi-billion euro arbitration in Stockholm against Gazprom allowing it to tear up dormant gas supply contracts and potentially setting a precedent for similar cases.

Europol Gaz's claim against Gazprom has been lodged in the same arbitration tribunal.

(Reporting by Julia Payne in Brussels and Marek Strzelecki in Warsaw; additional reporting by Jan Lopatka in Prague, Boldizsar Gyori in Budapest and Alexandra Schwartz-Goerlich in Vienna; Editing by Nina Chestney, Bernadette Baum and Susan Fenton)

By Julia Payne and Marek Strzelecki