Iraq restored partial operation at its Baiji oil refinery, the country's largest, on Monday, after a two-day shutdown due to a bomb attack, an official said.
"We have restarted production operation at 50 percent of the original capacity on Monday," said Abdul-Qader Saab, the refinery's deputy manager.
The refinery was shut down on Saturday morning after militants killed four workers and carried out a bomb attack, setting the facility on fire.
The militants planted explosives at a kerosene and benzene production unit at the northern refinery in the town of Baiji, a former al Qaeda stronghold 180 km (112 miles) north of Baghdad.
"We need at least 45 days to fix the production unit," Saab said, adding he expected a shortage in oil products needed for domestic consumption for the next 45 days.
"We (at Baiji) are in charge of supplying 11 provinces."
The remaining production units, which also produce kerosene, benzene and other oil derivates, at Baiji were not affected by the bombing attack.
In the southern town of Samawa, a second refinery was also restarted on Monday at full capacity of 30,000 barrels per day, after a two-day shutdown due to fire, oil ministry spokesman Asim Jihad told Reuters.
Iraq is considering to contact neighbouring countries and companies to import more fuel, Jihad said, without giving more details.
Iraq does not export any oil products as it uses all of its production for power generation and domestic consumption.
The country's capacity to refine fuels like diesel and gasoline has been ravaged by under-investment, and it has been forced since the 2003 US-led invasion to buy imported fuels to meet the growing gap between supply and domestic demand.
Baiji, which normally operates at about 70 percent of its 310,000 bpd capacity, produces 11 million litres of gasoline, 7 million litres of benzene and 4.5 million litres of kerosene a day. It was last shut in August for two days due to an electrical fault.