The world's top oil service company Schlumberger Ltd is expected to resume operations at Iraq's biggest oilfield next week following violent protests at the company's camp, a senior Iraqi oil official said on Thursday.

Thamir Ghadhban, chairman of the advisory commission to Iraq's Council of Ministers, told Reuters the situation at the BP-operated Rumaila oilfield in southern Iraq was now calm and it was safe for Schlumberger to get back to work.

"Schlumberger management is still on the ground and operations are expected to resume next week," said Ghadhban, speaking by telephone from Baghdad.

Schlumberger could not be reached for immediate comment.

The Iraqi official said there had been no reduction in production and exports during the incident. Rumaila pumps around 1.4 million barrels per day (bpd), more than a third of Iraq's total output of over 3 million bpd.

Dozens of angry Shi'ite Muslim workers and tribesmen stormed the Schlumberger camp in North Rumaila and wrecked offices early on Monday after accusing a foreign security adviser of insulting their religion, police and employees at the field said.

Oil officials and workers at the Schlumberger drilling site said the problem started when a security adviser they identified as British asked Iraqi workers to take down a flag and banners depicting a figure revered by Shi'ites.

"The Iraqi government will not allow anyone to take the law into their own hands and stringent measures have been taken to ensure the safety of all foreign personnel and the security of all oil operations," Ghadhban said.

"At the same time, the foreign workers must respect the religious traditions of the Iraqi people."

According to workers and officials, when the workers refused to remove the banners, the security adviser went to do so himself and tore one portraying Imam Hussein, whose death more than 1,000 years ago is currently being commemorated by Shi'ites across the world in rituals known as Ashura.

Officials were unable to comment on the resumption of work by Baker Hughes Inc, also hit by the protests.

On Saturday, an Egyptian worker hired by the U.S. service company to work at a drilling rig in Rumaila removed and tore a flag also depicting a holy Shi'ite figure, prompting Iraqi authorities to terminate his residency and expel him from the country, oil officials said. – Reuters