Iraq's main oil export terminal is still shut after being targeted in a suicide boat attack on Saturday, the Iraqi oil minister has said.
Attacks on oil supplies have plagued Iraq's reconstruction
Ibrahim Bahr al-Ulloum said the al-Basra terminal had suffered a power cut and would not resume operations until Monday at the earliest.
He said a smaller terminal, Khor al-Amaya, had reopened on Sunday.
Exports stopped after three boats blew up near the terminals, but no major structural damage was reported.
The disruption at al-Basra means a loss of nearly one million barrels a day in exports.
Earlier, Iraq's oil marketing chief Shamkhi Faraj said two tankers were loading at al-Basra and another at Khor al-Amaya.
The vital terminals jointly export 1.6 million barrels daily.
"The order was issued earlier today to resume pumping and loading is normal," said Mr Faraj, head of the State Oil Marketing Organisation.
But he said there would have to be "more safeguards and more patrolling" after the boat attacks.
The two terminals lie about 160km (100 miles) from the Iraqi port of Umm Qasr, which remained open after the attack.
Two American sailors were killed and five were injured when they tried to board one of the intercepted boats. A third US sailor died of his wounds on Sunday.
It was the first maritime attack on Iraqi oil installations since the March 2003 US-led invasion of Iraq, but onshore oil pipelines have been targeted repeatedly by saboteurs.
One official described the vessels as "suicide speedboats".
The US military says a team of investigators will try to establish the launching point of the attacks.
An eight-man coalition interception team was approaching one of the boats when it exploded, flipping the coalition boat and killing two crew members, said the US navy's Bahrain-based Fifth Fleet.
Five other crew were injured, said a spokeswoman.
The blasts came at the end of a grim day of attacks and explosions across Iraq, in which scores of people died.
As a target, the Basra terminal had everything, says the BBC's Lucy Williamson. Not only politically important, the oil exported through the southern port of Basra is economically crucial to the country.
It is also symbolically linked in the minds of many Iraqis to the reasons behind the invasion, she says.
The attack appeared to resemble the October 2000 bombing of the warship USS Cole off Yemen, when 17 US sailors died.
In that incident, blamed on al-Qaeda, two suicide bombers rammed a small boat packed with explosives into the side of the ship as it was refuelling.