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By Simon Shuster

MOSCOW (Reuters) - Bank of New York Mellon Corp (BK.N: Quote, Profile, Research) fought on Monday for the dismissal of a $22.5 billion Russian lawsuit, questioning the size of the claim and arguing that a Russian civil court cannot enforce U.S. criminal laws against it.

Judge Lyudmila Pulova did not rule on any of the motions, giving the Russian lawyers until May 13 to prepare a response.

Since last May, Russia's Federal Customs Service has been seeking compensation from the bank after a vice president was convicted in the United States for helping launder more than $7 billion from Russia between 1996 and 1999.

Bank of New York Mellon also sought to reassure investors that an adverse decision in the case would not materially affect it. In afternoon trading, the company's shares were up $2.07, or 5.1 percent, at $42.75.

The Russian side, applying the U.S. Racketeering Influenced and Corrupt Organizations Act, or RICO, has said it is entitled to triple the value of all the money laundered.

The bank's chief lawyer, Ivan Marisin, attacked this claim on two fronts.

He said that RICO, a law adopted to combat the Mafia, could not be applied by a Russian civil court. The lawyer also argued that triple damages were groundless, contending that "not a single document has been presented to prove any losses suffered by the Russian Federation."