LISBON, April 28 (Xinhua) -- Power supply is gradually being restored across Portugal following a nationwide blackout that lasted several hours, with approximately one-third of users having their electricity service resumed.
Portuguese Prime Minister Luis Montenegro said at a press conference that full restoration of the national power supply is expected within the next few hours.
According to the national grid operator, as of 9:30 p.m. local time (2030 GMT) on Sunday, power had been restored to more than two million customers, roughly one-third of the country's 6.5 million electricity users. However, authorities could not yet predict when full restoration would be achieved.
Under the national grid operator's plan, power is being restored progressively from north to south. Most areas of Porto and Lisbon have already regained electricity, and operations at Lisbon, Porto, and Faro airports have resumed.
Montenegro explained that the blackout, which began around 11:30 a.m. local time (1030 GMT), was triggered by an issue in the Spanish power network.
"The failure is related to an abrupt surge in voltage within the Spanish grid, the origin of which we have not yet been able to determine," he said.
However, the prime minister noted that the recovery of power supply in Portugal could take longer than in Spain, due to Portugal's grid being connected solely to its neighboring country.
He also said that the government is closely monitoring the restoration process and urged the public to moderate their electricity consumption during this period.
Spanish Prime Minister Pedro Sanchez has said that Spain's grid operator had restored power to about half of the affected areas nationwide.
The government's objective is "to continue restoring supply throughout the coming night," Sanchez said Monday night, noting that it will do so through interconnections with France and Morocco, combined-cycle gas plants, and hydroelectric plants.
The Prime Minister said that "no hypothesis" has been ruled out as to what could have caused the outage.
Senior officials from the European Union have ruled out a cyber attack as the cause of the blackout. Antonio Costa, President of the European Council, said on his social media platform X account that "at this point, there are no indications of any cyber attack."
