Deloitte's US financial advisory unit is to pay a $10m (£6.4m) fine and refrain for one year from new business with certain New York banks as part of an agreement to settle accusations over its review of money laundering controls at Standard Chartered Bank.
New York state's Department of Financial Services said Deloitte's financial services advisory group, which is separate from its auditing arm, must also undertake reforms to address potential conflicts of interest.
The state department said Deloitte, which was working as a consultant to Standard Chartered, omitted critical information in a report to regulators on its independent review of the bank's anti-money laundering policies.
Last year, Standard Chartered agreed to pay a total of $667m (£426m) to various US agencies to resolve allegations it had broken US sanctions against Iran and other countries.
The regulator said Deloitte also violated New York banking law giving Standard Chartered confidential reports involving suspicious activity the firm had prepared for other banks who were clients.
The settlement agreement said the regulator found no evidence the consultant intentionally helped or conspired with the bank to launder money.
In a statement, Deloitte said it was pleased the agency found no evidence it 'knew of, or aided, abetted or concealed any alleged violation of law' by Standard Chartered.