(Reuters) -When the CEO of Russian state gas giant Gazprom, Alexei Miller, opened a lavish Italian palazzo-styled building in central St Petersburg to house the company's export arm 11 years ago, he augured a future funded by European sales.

Russian and European officials say the US is exploring ways to work with energy giant Gazprom PJSC on global projects, a step toward forging closer ties with the Kremlin while trying to broker a peace deal on Ukraine.

The claims stem from Gazprom's decision to drastically reduce gas deliveries to Europe in 2022 after Russian President Vladimir Putin demanded that payments be made in rubles.

"According to Gas Infrastructure Europe (GIE), as of February 28, the last day of the calendar winter, 39.2 billion cubic meters of gas remain in European underground storage facilities. This is 38.5% of the storage volume and 24.3 billion cubic meters less than a year ago," the company reports.

European energy companies have filed lawsuits against Gazprom, seeking a total of €18 billion in compensation for the termination of gas supplies. This amount is nearly double the Russian energy giant's available cash reserves.

When the CEO of Russian state gas giant Gazprom, Alexei Miller, opened a lavish Italian palazzo-styled building in central St Petersburg to house the company's export arm 11 years ago, he augured a future funded by European sales.