Updated

Britain's Airport Commission has rejected a plan to build a four-runway airport in the Thames Estuary, describing it as more problematic and more expensive than other options.

The commission said Tuesday it rejected the estuary proposal pushed by London Mayor Boris Johnson because it would cause economic disruption and because environmental hurdles may make it impossible to deliver.

The commission, headed by Howard Davies, is examining how to best expand Britain's airport capacity amid growing international competition. Heathrow, once the world's biggest hub airport, has argued it needs to add at least one runway to be competitive.

Johnson says he'll fight on for the idea, arguing that "in one myopic stroke the Airports Commission has set the debate back by half a century."

Three proposals remain under the panel's consideration.