A fire at a power station on Thursday night (11pm local time) led to the closure of London Heathrow Airport in Great Britain today, disrupting hundreds of international flights.

"Due to a fire at an electrical substation supplying the airport, Heathrow is experiencing a significant power failure. To maintain the safety of our passengers and colleagues, Heathrow will be closed until 23:59 on March 21," reads a note from the airport published on the X platform.

A transformer at an electricity substation in Hayes, in the west of the city, caught fire, according to information from the local fire department. The fire was brought under control and no casualties were reported.

Heathrow Airport processes around 1,300 flights a day, according to Eurocontrol. And, according to a travel consultant, the closure could cost more than 30 million euros a day (20 million pounds).

"A backup should be fail-safe in case the main system is affected. Heathrow is such a vital part of the UK's infrastructure that it should have fail-safe systems," said Paul Charles, quoted by CNN Brazil.

"Even if the airport opens, we hope, by the end of Friday, there will be an impact on the operation for several days, because when aircraft are grounded somewhere away from an operation, they are stuck there with the crews operating the flights and, of course, the customers, until those crews have left to take their legally required rest periods," said independent air transport consultant John Strickland.

"And if the planes don't return, they won't be able to make the next flights, which means we'll have cancellations in the coming days."