TRIPOLI (Updated 3) - A Libyan-owned ship carrying a cargo of imported petrol has docked at a government-controlled port, helping to relieve a fuel shortage, a Libyan government official and an energy industry executive told Reuters. They said the ship was owned by the Libyan state shipping company and was unloading its cargo at the port of Zawiyah, 50 km (30 miles) west of Tripoli. They did not say where the vessel had come from. The Libyan official, who did not want to be identified, said the vessel was carrying 23 million litres of fuel. "The boat has now arrived," he said. Although Libya is an oil exporter, international sanctions and disruption caused by an uprising against Muammar Gaddafi's four-decade rule have hit fuel supplies and led to long queues at petrol stations. It was not immediately clear how the vessel had been able to get through a cordon of NATO warships which is patrolling Libya's coast to help enforce international sanctions. The Libyan energy industry executive, who works for a company involved in fuel distribution, said the arrival of the vessel was "a good step" in easing the shortages but he said it would only be a temporary solution. "We do not know if there is a plan to bring more fuel, or if it is only this ship," the executive, speaking on condition of anonymity, told Reuters.