Heathrow airport reported its passenger numbers fell by 5.3% last month because of the war in the Middle East.
The west London airport said 6.7 million passengers passed through its four terminals in April.
That is compared with 7.1 million during the same month last year.
The reduction reflects “the ongoing impact of the Middle East conflict on some markets and short-term adjustments to travel plans”, the airport said.
Heathrow chief executive Thomas Woldbye said: “We know passengers want certainty when planning their hard-earned summer holidays, so we are supporting Government and airlines as they work through their plans to get passengers on their journeys.
“While we have seen some short‑term disruption linked to the Middle East conflict, demand for travel remains strong with current fuel supplies stable.
“April was still our busiest month so far this year, underlining the strength of a global hub airport that can adapt quickly in times of uncertainty.”
Heathrow said it will update its 2026 passenger forecast in June “in light of the Middle East conflict”.
The airport insisted “underlying demand remains resilient” as it noted its number of transfer passengers in April was 10% higher than the same month last year.
It attributed this to an increase in passengers flying into Heathrow and then boarding flights to Asia and Oceania.
Middle Eastern airports are a major hub for these journeys, but many passengers are avoiding the region because of the conflict.
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