Russia’s Federal Customs Service is seeking $22.5 billion in damages from the Bank of New York Co., the world’s second-largest custodian of investor assets, for alleged money laundering in the 1990s.

The bank “committed violations of Russian law that resulted in damages of $22.5 billion to the state” between 1996 and 1999, a lawyer for the service, Maxim Smal, said by phone after filing the lawsuit in the Moscow Arbitration Court yesterday.

The head of the Customs Service’s legal department, Andrei Stukov, confirmed the amount of damages sought via a spokeswoman.

Mr. Smal said the suit is “almost entirely based” on an American investigation that ended in 2005 with the bank agreeing to pay $38 million to settle two criminal probes and admitting it failed to report $7 billion in suspicious Russian transactions.

The American probe “uncovered very serious violations,” Mr. Smal said, declining to elaborate, saying more details will be revealed at a news conference in Moscow today.

Founded in 1784, eight years after the signing of the Declaration of Independence, Bank of New York sold its branches in October and two months later agreed to merge with Mellon Financial Corp. to create the world’s largest custody bank. It has a market value of $31 billion and is the depositary for more than 1,250 U.S. and global depositary receipt programs, including Russia’s VTB Group, the state-run bank that raised $8 billion last week.

The bank, which said it hadn’t received official notification of the suit, called it “totally without merit.”

Lawyers representing the agency had approached it and offered to settle out of court for a “tiny fraction of the amount now claimed,” the bank said in a statement.

A former Bank of New York vice president based in London, Lucy Edwards, and her husband Peter Berlin, who ran companies with accounts at the bank, admitted in 2000 to conspiring to use the bank to launder more than $7 billion from Russia. The two Russian émigrés were sentenced last year to five years of probation after cooperating with New York federal prosecutors investigating international money laundering.

“This should be no surprise to the Bank of New York,” an attorney at Miami-based Podhurst Orseck PA, who is representing the Russian government in the case, Steven Marks, said in a telephone interview.

A Russian court can as much as triple the amount laundered by the Bank of New York to calculate damages incurred by the Russian Government, Mr. Marks said. The Russian government didn’t benefit from the 2005 settlement and has yet to recoup its losses, Mr. Marks said. Ms. Edwards is helping Marks with the case.

“Either the bank looked the other way or it knowingly participated for profit,” Ms. Marks said.

Swiss authorities opened an investigation in 2000 into allegations that a $4.8 billion loan to Russia from the International Monetary Fund in 1998 was laundered through Swiss banks and the Bank of New York. Nobody was charged in the case.