London’s Heathrow Airport has announced a 10 per cent increase in transit passengers during March as the US-Iran war forced Gulf countries to close their airspace, AFP reports.

Total passenger numbers, including those using Europe’s busiest airport to transit, climbed 6.9pc 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.

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