WASHINGTON - Credit Suisse Group has agreed to pay $536 million to settle a Justice Department probe and admit to violating U.S. economic sanctions by hiding the booming illegal business it was doing for Iranian banks.

The Justice Department announced the settlement yesterday, saying it was the biggest forfeiture ever against a company for violations of that type.

"Credit Suisse's decades-long scheme to flout the rules that govern our financial institutions robbed our system of the legitimacy that is fundamental to its success," Attorney General Eric Holder said at a news conference.

The $536 million that Credit Suisse is forfeiting will go to the U.S. government and the District Attorney's Office in Manhattan, which also participated in the settlement talks with the bank along with the Federal Reserve and the Treasury Department.

The bank, one of Switzerland's largest, has been under criminal investigation for years over business it did with countries subject to U.S. economic sanctions.

"Credit Suisse is committed to the highest standards of integrity and regulatory compliance in all its businesses and takes this matter extremely seriously," the bank said in a statement yesterday.