Heathrow faces falling further behind Europe rivals without being allowed to expand soon.
The warning came as the London hub handled a record 5.4 million passengers in February – up 2.4% year-on-year.
Emerging markets were a key source of growth with South Asia up 12.7% and Latin America up 6.5%, boosted by airlines flying larger, fuller aircraft to Heathrow
Domestic routes also grew strongly in February, up 3.6% as regional airline Flybe carried an extra 17,000 passengers on routes to Scotland in the month.
Heathrow chief executive John Holland-Kaye said: “Today’s figures show that Heathrow is filling up fast – if we don’t act soon to expand our nation’s global gateway, the UK will only fall further behind our European rivals.
“A prosperous, global-trading Britain needs an expanded Heathrow now.”
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