Some 6,000 passengers have “donated their kisses”, imprints of which have been used to recreate Pride’s iconic rainbow motif.

The flag is now flying above Terminal 2, and will remain in place until the end of July.

Heathrow unveiled the flag as part of a week-long celebration of Pride, with the airport expecting to welcome a 5% spike in passengers travelling to the capital for the event.

Its “kissing art” flag, created with kisses rather than brush strokes, features contributions by travellers from around the world.

The first kisses were added on July 1 when the flag canvas was placed in departures.

Passengers were provided with a choice of red, orange, yellow, green, blue or purple lipstick to make their mark.

The final kisses were added by staff from across the airport, its control tower, fire station and the British Airways crew centre, before being flown over Terminal 2.