British banking giant Standard Chartered is a repeat offender, at least in the eyes of New York’s top financial regulator, which fined the bank $300 million and suspended its ability to convert currency for violating a money laundering settlement.

On Tuesday, the New York Department of Financial Service said Standard Chartered had not flagged a series of wire transfers from clients and locales at high risk for money laundering, running afoul of a 2012 agreement the bank inked with the regulator. Back then, the bank shelled out a total of $667 million to state and federal authorities for allegedly processing $250 billion in transactions for Iranian banks in violation of U.S. sanctions.

Banks have software filters that identify electronic transactions involving entities and countries barred from the U.S. financial system. Because so much of the world’s financing flows through the United States, the prohibition makes it hard for countries and companies that are barred from doing business with U.S. firms.

New problems at Standard Chartered surfaced in a recent review conducted by an independent monitor who identified “high risk” transactions originating from Hong Kong and the United Arab Emirates. The monitor determined that the bank had an inadequate system in place to detect those problems, even though Standard Chartered had instituted new procedures in accord with the settlement. The bank, according to the monitor, did a poor job of auditing the system, leaving it vulnerable to lapses.

“If a bank fails to live up to its commitments, there should be consequences,” New York Superintendent of Financial Services Benjamin M. Lawsky said in a statement. “That is particularly true in an area as serious as anti-money-laundering compliance, which is vital to helping prevent terrorism and vile human rights abuses.”

Tuesday’s order calls for Standard Chartered to hold off on converting foreign currency into U.S. dollars through its New York branch for retail business clients in Hong Kong. This so-called dollar clearing is a critical step in transferring money to clients’ suppliers, processing loan payments and various other transactions.

Standard Chartered has also agreed to cut ties with some small and medium-sized business clients in the United Arab Emirates that are deemed high-risk. It will also be subject to two additional years of reviews by the monitor.

In a statement, the bank said it “accepts responsibility for and regrets the deficiencies in the anti-money laundering transaction surveillance system at its New York branch.” Standard Chartered said it has already begun “extensive remediation efforts and is committed to completing these with utmost urgency.”

The bank noted that the vast majority of its clients and businesses will not be affected by the order, but it promised to “work closely with the small proportion of clients in Hong Kong and the United Arab Emirates who will be affected.”

The latest punishment of the bank could do much more damage to its business than the 2012 settlement. Preventing an investment bank from engaging in one of its most basic business functions could result in the loss of customers and millions in revenue.

Lawsky exacted a similar punishment against France’s BNP Paribas, which plead guilty in June to concealing billions of dollars in transactions for clients in Sudan, Iran and Cuba in violation of U.S. sanctions. The bank agreed to pay $8.9 billion in fines to state and federal authorities and accepted a year-long suspension of its dollar-clearing operations.