For six years, a division of oil services company Schlumberger "willfully" violated U.S. sanctions against Iran and Sudan, the Justice Department said.

"Over a period of years [ending in 2010], Schlumberger Oilfield Holdings Ltd. conducted business with Iran and Sudan from the United States and took steps to disguise those business dealings, thereby willfully violating the U.S. economic sanctions against those regimes," U.S. Assistant Attorney General Carlin said in a statement.

The Justice Department said the oil services company agreed to enter a guilty plea and pay a $232 million penalty for conspiring to violate sanctions against trade with Iran and Sudan. Under the terms of the agreement, Schlumberger agreed to halt all activity in those countries for a three-year period.

Sudan split in two under a peace that, with the U.S. government's support, was meant to end a simmering civil war. While South Sudan gained control over oil when it gained independence in 2011, Sudan maintained control over the infrastructure needed for transit.

Iran, a member of the Organization of Petroleum Exporting Countries, is limited to six international oil customers according to a November 2013 deal with the nations party to ongoing nuclear negotiations. The government in Tehran said recently U.S. energy companies that moved against Republican leaders frustrated over the direction of the talks would be rewarded.

The Justice Department said the guilty plea shows the financial risk of skirting international sanctions. The plea concludes an investigation that began in 2009.

There was no statement from Schlumberger despite several outreach efforts.