LONDON, April 13, 2026 (BSS/AFP) - London's Heathrow Airport announced Monday a 10 percent increase in transit passengers during March as the US-Iran war forced Gulf countries to close their airspace.

Total passenger numbers, including those using Europe's busiest airport to transit, climbed 6.9 percent to 6.65 million last month compared with a year earlier, Heathrow added in a statement.

"While Heathrow's long-haul network absorbed demand in March, the outlook for the next few months remains uncertain", amid the conflict, said the airport's chief executive Thomas Woldbye.

Gulf airlines Emirates, Etihad and Qatar Airways have built their business model on connecting passengers on long-haul flights across the globe.

But following the outbreak of the war on February 28, Iran fired missiles and drones at Israel and US allies in the Gulf, reaching airports and other key infrastructure.

Iraq and Bahrain last week fully reopened their airspace amid the ceasefire agreed between the United States and Iran.

However, the United Arab Emirates and Qatar -- whose Dubai, Abu Dhabi and Doha hubs handle large quantities of long-haul flights -- have maintained many restrictions.

Despite the absence of a complete truce, "the knock-on impacts to global supply chains, including fuel, have not affected airport operations", Heathrow said Monday.