Chief Executive Thomas Woldbye said there was a queue of more than 40 carriers ready to start flying from Heathrow if they could get slots there. Woldbye added the time had come to unblock "a decades-old barrier to growth".

His comments come as parliament returns and as Heathrow prepares give evidence on its third runway plans following consultation on the Heathrow Expansion National Policy Statement.

Heathrow handled 23 million passengers between June and August this year, including 7.87 million in August alone. And while this represents a 2.1% year-on-year dip, the airport did record a new busiest-ever day on 2 August when nearly 272,000 passengers transited Heathrow.

The airport also retains its claim to being "Europe's most punctual hub" with 98% of passengers "waiting less than five minutes at security and 98% seeing bags depart as planned". This, it said, was achieved despite "some big challenges" for aviation during the summer.

After Xiamen Airlines became Heathrow's newest carrier this week, the airport said: "The number of incumbent and prospective airlines seeking scarce slots now exceeds 40. Three-quarters of proposed new routes would provide vital long-haul links, but Heathrow’s ability to accommodate them is constrained without expansion."

Heathrow claims expansion will support 108,000 jobs, boost trading capacity by 50% and make travel more affordable to more destinations.

Woldbye added: "This summer, Heathrow remained Europe’s most punctual hub. The longest queue at Heathrow is now the one made up of over 40 airlines that want to better connect the UK but can’t secure a slot because our runways are full.

"Expansion is a national project that will create jobs, unlock growth and make travel more affordable. We are working with government to deliver these benefits to every nation and region as quickly as possible."