Mayor of London Boris Johnson believes there are three ways to successfully enhance the UK's airport capacity - none of which involve expanding Heathrow.

Mr Johnson is not convinced that adding new runways to the busiest airport on earth is the best course of action.

Instead, he thinks a four-runway hub in the Thames Estuary, a new facility on the Isle of Grain or an extension of Stansted Airport would be more feasible.

The mayor believes Britain is in danger of falling behind other countries that are currently building "mega airports" unless action is taken soon.

"For London and the wider UK to remain competitive we have to build an airport capable of emulating that scale of growth," Mr Johnson remarked.

His comments are unlikely to gain favour with Heathrow chief executive officer Colin Matthews, who said last week that a single hub airport is required to maintain the UK's position in the global aviation race and that expanding the London facility is the only sensible option.