Iraq briefly suspended oil loadings on Thursday after a drone hit an oil tanker at its Basra terminal, four Iraqi oil and security sources told Reuters, before later resuming them.
The drone did not cause damage or fire and it was not immediately clear who launched it, the sources added.
In a statement the oil ministry said reports of a halt to crude exports from the southern ports due to an alleged drone attack were inaccurate, and that loading operations were continuing as normal.
The ministry said its investigation found the incident involved a tanker reporting the sighting of a foreign object in its vicinity, and that no fire or damage to the vessel had occurred.
The incident was not a direct attack on the Basra terminals or vessels there, the head of Iraq's state oil marketer SOMO told Reuters.
"It is not targeting Basra Oil Terminal. Its target is another place. Loading is at normal rates depending on the vessels' availability," Ali Nazar said.
The oil tanker was towed outside the port along with another tanker that was anchored as a precautionary measure, the four sources said.
On Wednesday, a drone came down in Iraq's Faw port without causing any damage, the state news agency reported, without giving further detail. Operations at the port were not affected.
Separately, Dana Gas said on Thursday it had shut down the main production facilities at Iraq's Khor Mor gas field due to credible security threats and escalating regional tensions, adding that it was monitoring the situation, a company spokesperson said.
Gas supplies to power generation stations in Iraq's Kurdistan region have dropped by 2,500 megawatts as a result of the security threats at the Khor Mor field, the region's electricity ministry said in a statement.
The ministry said the disruption was temporary, and all parties were working to resume gas flows to power plants.
The Iran war has disrupted oil exports from Iraq's southern terminals due to the effective closure of the Strait of Hormuz.
Iraq, OPEC's second-largest producer, exported 10 million barrels of oil via the Strait of Hormuz in April, down from about 93 million per month before the war, according to oil minister Basim Mohammed.
Total June exports stood at around 24.5 million barrels, two oil officials told Reuters on July 5.
Iraq has also been exporting via Turkey using the northern Kirkuk-Ceyhan pipeline and has sought to export oil through Syria.
Baghdad has been striving to balance its ties with neighbouring Iran and the US amid the military escalation between the two.
However, Tehran has launched attacks against Iranian Kurdish opposition groups in northern Iraq, while Iran-backed militants in Iraq have launched attacks against Persian Gulf neighbours.
(Reporting by Aref Mohammed in Basra, additional reporting by Muayad Hameed in Baghdad and Ahmed Ghaddar in London; writing by Nayera Abdallah; Editing by Mark Potter, Jason Neely and Jan Harvey)