Chevron Corp. removed its expatriate staff operating in northern Iraq as a security precaution, a spokeswoman said on Jan. 6, joining other oil companies pulling staff following the U.S. killing of an Iranian general in the country.

U.S. officials last week called for American citizens to leave Iraq hours after a drone strike killed Iranian Quds Force leader Qassem Soleimani and Iraqi militia commander Abu Mahdi al-Muhandis.

Chevron said a small contingent of expatriate employees and contractors temporarily left its Kurdistan region operations as a precautionary measure. Other U.S. and foreign oil and service companies have withdrawn dozens of workers since the weekend.

The U.S. major has a small operation in Iraq that is expected to begin producing 20,000 barrels of oil per day by mid-year. Operations are continuing with local staff and expatriates working remotely, the Chevron spokeswoman said.