Tony Brown
BBC World Service

Back in the Portuguese capital of Lisbon, streets are choked with traffic. Police officers have taken over from not-working traffic lights, using whistles and hand signals.

Traffic lights stopped working across the city at lunchtime.

There are huge queues for the buses and the metro is closed. People are waiting in the hot sunshine under umbrellas.

One lady I spoke to under her umbrella says she is a dentist and was treating a patient when the power went off. She’d already been waiting two hours for the bus.

Pedro Sánchez also asks the public to use phones "responsibly" and says this is a critical moment for telecommunications in the country.

He urges people to only use phones for brief calls and necessary communication as the system is being fully re-established.

Sánchez says there will be increased presence of security forces in the streets, but that the outages have so far not caused any security issues across the country.

Hospitals are functioning and vulnerable people are being treated at their homes, the Spanish PM goes on to say, adding that ports have not reported any incidents, that air traffic has been reduced and train traffic halted for security reasons.

Sánchez continues, saying electricity has been restored to some areas in the north and the south of Spain "thanks to help from France and Morocco".

Earlier, the Spanish grid operator said that power was being restored "in several areas of the north, south and west of the [Iberian] peninsula".

"We urge you to turn to official channels for information," Sánchez goes on - imploring people in Spain to avoid falling "for disinformation".

Spain's Prime Minister Pedro Sánchez is now giving an update to reporters.

He says the cause of the power cut is still unknown and warns against speculation.

No cause can be discredited at this point, he adds.

Image source, Reuters

Spain's Transport Minister Oscar Puente has said it is not likely that medium and long-distance trains will resume normal service today.

He adds that the intention is to resume shorter distance commuter services as soon as the electricity supply has been restored.

Work is also under way to rescue those trapped on stranded services.

Puente says recovery of control systems will take time after the electricity supply has been resumed and trains will also need to be repositioned.

The aim will be to resume service for tomorrow if the supply is restored today.

Replying to a user of the social media platform X, Puente also says air traffic is currently operating at "80% of its capacity".

The 20% reduction is due to security precautions relating to telecommunications.

Barbara Tasch
Live reporter

Image source, Cara McGoogan

I have been speaking to Cara McGoogan, who is in the Carcavelos suburb of Lisbon and tells me that there has been a run on local grocery stores.

Supermarkets have shut as their doors all run on electricity and are heavily air conditioned.

"The local grocery store is still open, but it's really full," Cara says, describing a chaotic situation with the store quickly switching to cash as card payments stopped working. Cashiers were using the calculator on their phones to figure out what change to give, she says.

Cara, who is currently on holiday in the Portuguese capital, adds that they managed to buy some canned goods and vegetables and also bought some candles and battery-powered lights and torches.

All electricity has gone, she says, including power to fridges and freezers. They luckily have a gas-powered barbecue, so friends and neighbours are coming over tonight with all their perishables and they plan on cooking everything.

The blackout started around 11:50 local time (10:50 BST), Cara adds, and while phones were initially fine, the 5G networks are only working intermittently now and the lines went down fully for some time as well.

We were expecting to hear from Spain's Prime Minister Pedro Sánchez about the power cut a while ago - at 17:15 local time (16:15 BST) - but the news conference is yet to start.

We'll bring you the latest lines from him as soon as we have them.

Spain's nuclear reactors are in "safe condition" despite the country's power outages, Spain's nuclear safety council says.

The reactors automatically stopped working after the outage but emergency generators kicked in.

The shutdown was in line with the way in which Spain's power plants are designed to respond to an unexpected power outage, the council adds.

Here are some of the latest images we've been seeing showing the fallout from the power outages across Spain and Portugal.

Image source, EPA

Image source, Reuters

Image source, Getty Images

Image source, EPA

Image source, EPA

Image source, Reuters

Portugal's Prime Minister Luis Montenegro says there is "no indication" that a cyber attack is behind the power cut impacting Portugal and Spain.

Speaking to journalists, he says the cause of the power cut is still unknown but it is now clear that it "did not originate in Portugal".

He says he expects electrical power to return to Portugal "in the coming hours".

Montenegro says he is taking a break from a ministerial meeting about the incident to visit Portuguese power firm REN to find out more.

The grid operator earlier said "extreme variations" in Spain's temperature caused the power failure, according to Reuters news agency.

We can now bring you the latest from the organisers of the Madrid Open tennis tournament, which was disrupted by the power cut earlier.

Organiser say "in order to guarantee general safety, the nationwide power-cut experienced in Spain on Monday 28 April has forced the cancellation of both the day and night sessions at the Mutua Madrid Open".

Image source, Reuters

Here's more now from the new statement from Spanish grid operator, Red Electrica.

The statement adds that work is under way to "gradually" recover electricity throughout the Iberian peninsular.

Voltage has already been recovered in some areas - and consumers will start to see supply returning, it says.

The Spanish grid operator has said that power is being restored "in several areas of the north, south and west of the [Iberian] peninsula".

Raphael Sheridan
Reporting from Malaga

Image source, Raphael Sheridan/BBC

I'm currently in staying in an apartment in Malaga - some bars and restaurants here have stayed open here benefitting from the glorious weather.

At 15.43 local time (14.43 BST), the apartment's oven and washing machine suddenly started chirping, and a man on the street below me whooped.

Power has, it seems, returned to Malaga.

For about an hour I had been without phone service or internet - and therefore completely cut-off from the world - which leant an uneasiness to an otherwise sunny, peaceful day.

The hope here is that the lights now stay on.

French grid operator RTE is helping supply Spain's electrical network, it says.

RTE says it has already re-supplied 700 MW of Spanish consumption and it will increase aid as soon as the Iberian grid can receive it.

There is no current impact in France, the company says, adding that all power has been restored to homes in the French Basque Country that were left without power earlier today.

Meanwhile, Ukraine's energy minister German Galushchenko says, external his country is "ready to assist in restoring the stable operation" of Europe's energy networks and will share "knowledge and experience".

Guy Hedgecoe
Madrid correspondent

I was on a train in Madrid at Chamartín station, one of the main stations in the city, when the outage happened.

A member of staff came on the train and told us to get off the train and evacuate the station. There's a huge crowd of people outside at the moment.

We know other rail services around the country have been affected - underground rails have been heavily hit.

Traffic lights also seem to be affected, certainly in the bigger cities, so this all creates a certain amount of chaos.

People are desperate to find out if they can get back on their trains, if there's going to be any service later today - there's just a great deal of uncertainty.

James Kelly
BBC News

Image source, Tom McGilloway

Tom McGilloway, 31, is on holiday in Lisbon visiting members of his partner's family.

They are due to return home to London tonight but are not clear whether their flight will be affected.

"It’s a strange vibe because everyone’s aware there is chaos and you can’t get public transport, no one knows what’s going on at the airport," he tells me this afternoon.

"A lot of the restaurants and the shops can’t take payments because they have wired terminals, so it’s meant that everyone’s flooded out of main areas to a lot of the pop-up vendors."

He says for the time being people are getting drinks and food - but vendors have told him they will only be able to keep working until the batteries run out on their payment terminals.

"If I need to book a hotel if the plane is cancelled, I don’t know how I can do it if payments are down," he adds.

"My partner’s parents are trying to get petrol so they can pick us up to take us back to Alentejo but many petrol stations are closed or not taking payment. We might be stuck with no plan for where to stay tonight."

• We heard earlier from someone else in Spain, Lesley, who said her husband was driving around Murcia "trying to find a petrol station that's open to get petrol for the generator so that we can plug in the fridge"

“Power outages in Portugal and Spain are impacting access to some airports and affecting some airports operations including Lisbon, Madrid and Barcelona," easyJet says in a statement.

"Like all airlines, we are experiencing some disruption to our flying programme meaning that some return flights from Lisbon and Madrid have been unable to operate," the airline goes on, adding: "Our flying programme at Porto and Faro airports is operating as planned."

The flight operator tells passengers to check local travel advice and their flight tracker for more information.

They also say passengers in Spain or Portugal who are unable to travel are being provided with free of charge transfers within 72 hours, or a flight voucher.

Image source, Getty Images

In an update, Spain's power company says voltage has been restored in certain substations in areas of the north, south and west of the country.

"We continue to work with all resources to achieve the restoration of supply as soon as possible throughout the entire territory," Red Electrica says.

But in an update of its own, Spain's national railway firm Renfe says all services are still suspended "due to power outages".

Meanwhile, Madrid Metro service says all its lines also remain closed.

We're now hearing from Antonio Costa, President of the European Council, who says there are no indications that today's power outage has been caused by a cyber attack at this point.

Costa says he is in touch with Spanish Prime Minister Pedro Sánchez and Portuguese PM Luís Montenegro - with grid operators in both countries "working on finding the cause, and on restoring the electricity supply".