Bulgaria's state-owned gas supplier Bulgargaz said Tuesday it was taking Gazprom to court and seeking millions of euros in damages over the Russian company's cut of supplies after its invasion of Ukraine.Bulgaria, which was almost totally dependent on Russia for its gas, and Poland were the first EU countries that saw their supplies halted after refusing to pay for the gas in rubles as demanded by Moscow in response to Western sanctions.Two months ago Bulgargaz invited Gazprom to settle the dispute out of court."As the Russian side did not take any action to resolve the issue out of court, Bulgargaz took the necessary steps to protect the company's interests," the group said in a statement on Tuesday.It added that it had launched legal proceedings on Monday before the Court of Arbitration at the International Chamber of Commerce in Paris, claiming over 400 million euros ($432 million) in damages over gas that had not been delivered between the cut in late April 2022 and the expiration of its contract in end-2022.Before the abrupt halt, Bulgaria received 90% of its gas from Gazprom.Since then, the country had to urgently find supplies from other sources.It now covers a third of its annual consumption of about 3.0 billion cubic meters of gas through imports from Azerbaijan and buys liquified natural gas from the United States and the Middle East through terminals in neighboring Greece and Turkey.It also signed in January 2023 a long-term agreement with Turkey's Botas, giving both countries access to their gas infrastructure, which Sofia had recently sought to have reviewed.Meanwhile, Gazprom's main customer in Germany, Uniper, won the right in June to claim "more than 13 billion euros" in compensation for gas supply cuts by its former Russian partner since mid-2022, following a favorable ruling by an arbitration tribunal in Stockholm.The total halt in deliveries had brought the group to the brink of bankruptcy and the German government rescued it by nationalizing it.Another German energy company, RWE, has also filed a suit against Gazprom over the cuts.