Spain and Portugal are racing the setting sun as they respond to a massive, unexplained power outage that knocked out traffic lights, caused chaos on roads and in airports, and threatened to plunge tens of millions of people into darkness on Monday.

The UK Foreign Office has issued a travel warning to UK holidaymakers after widespread power cuts hit Spain, Andorra and Portugal earlier today.

A POWER outage across Spain and Portugal has resulted in flight cancellations at a number of airports, as well as huge delays and train station closures. Red Eléctrica, Spain’s national grid