MOSCOW, May 17 (Reuters) - A Russian court has ordered that UniCredit's assets, accounts, property and shares in subsidiary companies be seized as part of a lawsuit involving the Italian bank, according to court documents.

The ruling by a St Petersburg arbitration court covers 462.7 million euros ($503.28 million) in securities, real estate and accounts belonging to UniCredit as well as 100% of shares in UniCredit Leasing and UniCredit Garant.

There was no immediate comment from UniCredit.

UniCredit was one of the guarantor banks under a contract for the construction of a gas processing plant with Germany's Linde, which was terminated due to Western sanctions.

($1 = 0.9194 euros) (Writing by Mark Trevelyan, Editing by Louise Heavens)