Britain is trying to decide how to expand its airport system which is currently running at full capacity in the south east.

Under consideration are a third runway for Europe's busiest airport, Heathrow, a second runway at London Stansted, or a new airport in the Thames Estuary.

Writing in the Daily Telegraph Tim Yeo, Britain's former environment minister who was previously a high-profile opponent of the third runway, said the "environmental objections" to the expansion of Heathrow were "disappearing".

Heathrow is operating at full capacity after Britain's Conservative-led coalition government blocked development of a third runway when it came to power in 2010 as further expansion of the west London site would mean a huge increase in the number of planes flying directly over the capital.

Yeo, who also chairs parliament's energy committee, claimed backing the expansion would give the coalition government a "sense of mission".

"The prime minister must ask himself whether he is man or mouse," wrote Yeo.

"An immediate go-ahead for a third runway will symbolise the start of a new era, the moment the Cameron government found its sense of mission. Let's go for it."

BAA, owned by Spain's Ferrovial (FER.MC), believes Heathrow is falling behind rival European airports in the battle for lucrative routes to China because of the constraints on growth at Britain's largest airport.

Britain will launch a consultation document on "sustainable aviation" later this year. BAA is expected to lobby again for a third runway. (Reporting by Rhys Jones)

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