A tanker carrying Iraqi Kurdish oil has that had been anchored off the coast of Texas has disappeared from satellite tracking.
The United Kalavrvta tanker, loaded with $100m of crude oil exported from Iraqi Kurdistan, had waited off the US coast after Baghdad launched a legal challenge to prevent the oil from being sold in the US.
Reuters news agency cited ship-tracking data that showed the tanker, which had been carrying one million barrels of oil, had disappeared from the radar.
A number of tankers carrying disputed Iraqi Kurdish crude oil have turned off their tracking systems in recent weeks, as they offloaded their cargoes around the world.
One such case involved the Kamari tanker, which had been tracked to an area north of Egypt's Sinai Peninsula in August. After going dark, the vessel reappeared on ship tracking systems off the Israeli coast two days later without a cargo.
Baghdad has fought attempts to sell oil independently of central government, accusing the Kurdistan Regional Government (KRG) of piracy.
Infuriated by the Kurds' efforts to export the oil, Baghdad has launched legal action against Turkey over its role in the oil sales, while it sent out warnings to governments over its objections to sales of Iraqi Kurdish oil.
Iraq filed a lawsuit with an American court which initially issued an order to seize the United Kalavrvta tanker's cargo if it entered US territory but the court subsequently threw out the order.
Meanwhile, Reuters reported that Iraqi Kurdistan has shipped more than eight million barrels of oil from the Turkish port of Ceyhan since May.
An oil pipeline that runs from the semi-autonomous region to the Turkish border was completed early in 2014, although exports from Turkey did not start until May as Arbil and Baghdad disputed the rights to sell oil produced in KRG territory.