Heathrow said passenger numbers fell last month despite notching up its busiest ever day in May amid an ongoing impact of the Iran war on international travel.
The west London airport said 7.1 million passengers passed through its four terminals in May, down 1.2% year-on-year.
UK passenger numbers fell 1.9%, while those from the Middle East were 31% lower as the Iran war continues to impact the global travel sector.
open image in galleryBut the decline marks an improvement on the 5.3% drop seen at the airport in April, when it said the conflict had caused some “short-term disruption”.
The group said it achieved its busiest ever day for the month of May, with 262,000 passengers recorded on May 22, at the start of the school half term holidays.
Heathrow – which last month celebrated its 80th birthday – said it had pressed ahead with investment plans, including kicking off upgrades to its terminal four car parks and check-in facilities.
It hit out at the Civil Aviation Authority (CAA), claiming the regulator was proposing cuts to its investment plans.
“While other countries expand their hub airports, the CAA’s proposed cuts to our investment plans risk taking the UK backwards and weakening our competitiveness,” it said.
open image in galleryThomas Woldbye, chief executive of Heathrow, added: “Heathrow has kept Britain connected for 80 years – but today we’re operating at capacity.
“Demand for travel and trade is strong, and passengers want more choice, better connections and good value.
“But both short and long-term growth of the UK’s only hub airport is at risk if the CAA delay necessary investment.”
Heathrow is hoping to secure planning permission by 2029 to build a third runway.