Using its New York-based operations, a major British bank schemed with the Iranian government for nearly a decade to launder $250 billion, leaving the United States financial system vulnerable to terrorists and corrupt regimes, New York’s top banking regulator charged on Monday.

The New York State Department of Financial Services accused Standard Chartered, which the agency called a “rogue institution,” of masking more than 60,000 transactions for Iranian banks and corporations, motivated by the millions of dollars it reaped in fees.

Senior management at the 150-year-old bank used the New York branch “as a front for prohibited dealings with Iran — dealings that indisputably helped sustain a global threat to peace and stability,” according to a regulatory order sent to the bank. The order requires the bank to explain the apparent violations of law in a hearing later this month and justify why its license to operate in New York shouldn’t be revoked.

The bank said Monday night that it “strongly rejects the position and portrayal of facts” by the agency.