West Bengal Chief Minister Mamata Banerjee's official visit to the United Kingdom was greatly delayed as a result of a fire at an electrical substation close to London's Heathrow Airport, which caused widespread disruptions. The March 20, 2025, fire caused a major power failure at Heathrow, the busiest airport in Europe, which led to the cancellation of more than 1,300 flights and inconvenienced about 290,000 passengers.

Originally scheduled to leave Kolkata on Friday night, Chief Minister Banerjee's flight was first rescheduled to Saturday morning and then to Saturday evening. She ultimately left on Saturday night at approximately 8:30 PM IST. Addressing the media at Kolkata's Netaji Subhas Chandra Bose International Airport before her departure, Banerjee acknowledged the disruption, stating, "As you know, we had a flight in the morning, but it had to be cancelled. This has disrupted the entire schedule. The trip has become very hectic, including two days of travel."

While on her UK visit, the Chief Minister is also set to give a lecture at the University of Oxford on March 27. She will also be part of a series of programs conducted by the Indian High Commission on March 24, a business summit on March 25, and a government-to-government program on March 26.

The blaze at the North Hyde electrical substation in Hayes, London, not only impacted flight schedules but also caused power cuts to about 16,300 households and disrupted train travel to and from Heathrow Airport. The accident has triggered British authorities to open an investigation into the energy resilience of the UK in a bid to avoid such incidents in the future.

In spite of the unexpected delay, Chief Minister Banerjee has promised that she will be in constant touch with her government in West Bengal while she is away, so that governance remains uninterrupted.