Spain's electricity grid operator Red Electrica said it was able to supply virtually all of the country's electricity demand early on Tuesday as the system gradually recovers from a nationwide blackout on Monday,

Spain's Interior Ministry on Monday declared a state of emergency after a nationwide power blackout hit most of the Iberian Peninsula. The ministry added the emergency status will be applied in the regions that request it.

Electricity returned to nearly all of Spain almost 18 hours after a blackout there and in neighboring Portugal. The cause of the outage was unclear.