Heathrow reported a 10% spike in transfer passengers last month caused by the war in the Middle East.
The west London airport said it “temporarily absorbed demand from elsewhere”, as the conflict led to widespread airspace closures.
About half a million passengers per day usually use airports in Dubai, Doha or Abu Dhabi, which are vital hubs for travel between Europe and the continents of Asia and Australia.
Heathrow said a total of 6.6 million passengers travelled through its four terminals last month.
This was a 6.9% increase from the same month last year, and represents the busiest March in its history.
But the airport warned “the outlook for the next few months is uncertain, due to the ongoing conflict”.
Heathrow said the impact of the war on the supply of jet fuel has “not affected airport operations”, adding that it will “monitor the situation and liaise with Government and airlines to protect passengers’ journeys”.
Thomas Woldbye, chief executive of Heathrow, said: “We’re doing everything we can to support airlines and passengers as travel trends shift during the Middle East crisis.
“While Heathrow’s long-haul network absorbed demand in March, the outlook for the next few months remains uncertain.
“I’m proud of what colleagues have achieved to quickly adapt and continue giving passengers a great service during difficult times.”
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