Despite pointing the finger at Ukraine during the recent gas dispute, Russia could be on the hook for millions of dollars in compensation after failing to meet energy commitments to freezing European nations.
Russian gas flow to Europe resumed this week after Moscow and Kiev signed a 10-year supply contract that the two parties insist will guarantee future shipments aren't interrupted.
But the standoff that has dented Russia's credibility as a reliable energy supplier and cost more than a billion dollars in export revenue could yet be more costly to Moscow if some of the worst-hit European countries seek damages from monopoly OAO Gazprom (GAZP.RS).
Bulgaria, which suffered most from the supply cuts, said it will file a claim against the state gas firm.
Friday, the country's Economy and Energy Minister Petar Dimitrov handed Gazprom's Deputy Chief Executive Alexander Medvedev an official request during talks in Sofia.
He didn't say how much Bulgaria was seeking in damages, but estimated total losses for around 360 industrial users at around $129 million, according to the Associated Press.
Other countries are likely to follow, with Medvedev meeting Slovakia's Prime Minister Robert Fico to discuss the same issue later Friday.
Earlier this month, Fico said Slovakia's economy lost EUR100 million daily due to the stoppage in gas flows.
Gazprom says it has no intention of paying up and that Ukraine is to blame.
"(Gazprom) isn't going to pay for any damages caused by the gas crisis," Medvedev said during his visit to Sofia. "All such claims should be sent to the Ukrainian side, who shut off the pipelines."
The Ukraine government press office could not be reached for comment.
Medvedev says Gazprom faced "force majeure conditions (that) made it impossible to fulfill our contract obligations. We did not have the physical possibility to supply gas to Europe."
But some experts disagree with Medvedev, saying European importers have agreements with Gazprom, not with Ukraine.
"All contracts say Gazprom has to deliver gas to a specific point west of Ukraine's border with the European Union," said Mikhail Korchemkin, an independent gas analyst based in Pennsylvania.
It remains unclear whether Gazprom would legally be able to redirect claims to Ukraine, as the company's European export contracts have never been made public.
Analysts struggle to predict how much claims for damages could eventually total, if Gazprom is held responsible for the losses.
But they reckon the monopoly is unlikely to pay unless forced to do so by a court.
"I don't think they'll just agree to any claims," said Pavel Kushnir, an analyst at Deutsche Bank in Moscow.
He says that while paying damages to Bulgaria alone may not amount to much for Gazprom, the picture may look different if claims build up from other nations.
Western European nations have so far been quiet on the issue of compensation, with many suffering far less than have the newer E.U. members.
Some, including Italy and Germany, enjoy friendly ties with Russia and may not want to rock the boat too much, especially with projects like the Nord Stream gas pipeline - set to bring Russian gas to Europe without passing through Ukraine - important to longer-term diversification plans.
European Commission President Jose Manuel Barroso indicated earlier this week that individual companies are free to sue Russia for the New Year disruptions. None have so far voiced any complaints.
"It could be a a mess," Kushnir said.