More than 99 percent of power networks in Spain were restored by Tuesday morning and most had “stabilised” in Portugal, according to the respective power operators, following Monday’s outage that stranded people in buildings, elevators and public transport and cut access to phones and the internet.

An unprecedented power outage across large parts of Spain and Portugal could last into Monday night, experts have warned. The outage has caused chaos in cities across Spain and Portugal, including capitals Madrid and Lisbon,