The airline joins "Club Madrid 2016", made up of leading Spanish and world corporate organisations including Telefonica, Repsol, Price and Accenture.

Up to 70 per cent of the bid’s budget is covered by these funds already pledged by corporate sponsors.

The partnership will help promote the Madrid candidacy throughout the world as Iberia launches a campaign to support the bid amongst clients and employees in September ahead of the International Olympic Committee at its Session in Copenhagen on October 2 on which city will follow London and host the 2016 Games.

Promotion of the Madrid bid will reach four million Iberia Plus members, the 335,000 people who visit the airline’s website each day, and over 22,000 employees who represent the company throughout the world.

Support offered by Iberia also includes a plane bearing the Madrid 2016 official logo to transport the official delegation to the Danish capital next month.

Iberia will also fly a second plane to Copenhagen to transport further members of the delegation and the media.

Mercedes Coghen, the chief executive of Madrid 2016, said: “Iberia is an ambassador for Spain throughout the world and we are delighted to have them as our sponsor.

"Our list of corporate partnerships is outstanding and very impressive.

"Their support underlines the extensive support we have from all corners of Spanish society for our bid.

"It shows how much everyone in Spain wants to host the best Games ever."

Besides Madrid, the other bid cities are Chicago, Rio de Janeiro and Tokyo.