Among the violations being investigated are Commerzbank's transactions for the Islamic Republic of Iran Shipping Lines.
News of the probe comes little more than a week after French banking firm BNP Paribas pleaded guilty to felony charges in a U.S. court.
The major French bank admits doing business with Iran and other U.S.-sanctioned countries, including Sudan and Cuba.
The French bank pleaded guilty to one count of falsifying business records and one count of conspiracy.
BNP is expected to plead guilty to a criminal charge in Manhattan Federal Court on Monday.
Mariam Yahya Ibrahim was detained at Khartoum airport Tuesday, a day after an appeals court overturned a death sentence imposed on her.
A U.N. panel has concluded a shipment of weapons seized by Israel came from Iran and represents a violation of the arms embargo on Iran.
BNP Paribas may enter a $9 billion settlement with U.S. authorities that could prevent it from making U.S. dollar-based transactions for months.
The bank is expected to admit it hid transactions that routed funds to sanctioned countries like Sudan, Cuba and Iran.
BNP Paribas has been negotiating on an almost daily basis with U.S. authorities for weeks.
French Foreign Minister Laurent Fabius says it will defend BNP Paribas against "unreasonable" U.S. penalty.
Till date, government ministers have said little in public about BNP Paribas' negotiations with U.S. authorities.
A Khartoum official tells BBC that the woman accused of apostasy is set to be freed "in a few days."
Many of the migrants have fled war zones and are seeking asylum in France or Britain.
Credit Suisse investors are confident despite a $2.5 billion fine and guilty plea, and analysts say this is the new normal for big banks.
Often ahead of its Western counterparts in investment, China is moving from natural resources into manufacturing and services.
Though raised a Christian and married to a Christian, Sudan sentenced her to death because she has not embraced her father's Islamic faith.
China's investment in a Kenyan railroad shows a superpower eager to capture African hearts and minds, but not quite succeeding yet.
The latest case will follow JPMorgan Chase, which paid $13 billion last year to settle mortgage-related charges, and HSBC, which paid $1.9 billion.
The trademark registrations are filed under “class 14,” a section that covers jewelry, clocks and watches.
More than 1 million people have been dislocated from their homes since December, and oil companies have been warned to pack up and leave.
Beijing's policy of nonintervention in oil-producing countries is becoming a bit more flexible.