Virgin boss Sir Richard Branson and union bosses have thrown their weight behind plans to create a new runway at Gatwick airport.

The announcement has intensified debate just days before the deadline for public comments on the plans.

It follows a proposal by South-East Euro MP Caroline Lucas to create a European-wide anti-expansion alliance to help give campaigners a voice against big business.

The TUC (Trades Union Congress) says new runways should be built at Gatwick, Heathrow and Stanstead to secure tens of thousands of jobs and keep the UK at the heart of air travel in Europe.

Its report, which is being submitted to the Government, said building new runways would not be popular with community and environmental groups but the cost of doing nothing was "too awful to contemplate".

TUC general secretary Brendan Barber said: "The future prosperity of the UK and the South-East are heavily dependent on the ability of our aviation industry to grow. If limits are placed on UK airports' growth, business will simply go elsewhere.

"Too many jobs and too much investment are at stake to allow the brakes to be put on expansion now."

TUC South-East regional secretary Mick Connolly said: "With the growth of low-cost airlines, more people are travelling by air, more frequently, than ever before.

"The Government's own figures show that a block on expansion could see the cost of air travel rising beyond the reach of ordinary working people, and a loss of 73 million passenger journeys. This cannot be allowed to happen."

Sir Richard's airline, Virgin Atlantic Airways, has called for the "earliest possible" development of a second runway at Gatwick, where Virgin runs 45 flights a week.

A spokesman said: "The construction of Cliffe and possibly of a mega-Stansted would do more harm to the environment than the development of Heathrow, Gatwick and more restrained development of Stansted."

Sir Richard said: "Business, tourism, trade unions, air users and the aviation industry all demand a clear commitment from Government to the development of new runway capacity and a detailed timetable for its delivery."

Meanwhile, Dr Lucas says the Euro-alliance is needed to beat the political influence of big businesses.

Anti-expansionists say environmental issues are often put in the shade by the huge figures bandied about by airlines in support of their industry.

Dr Lucas, a member of the European Parliament's environment committee, has championed the united approach with colleagues from Belgium and the Netherlands.

She is arranging a European conference in November to discuss the scheme.

She said: "There is massive pressure to expand and everyone ends up playing destinations off against each other. We need a united approach."

One of the plans would be to develop an aviation emissions charge similar to the one operated at Zurich in Switzerland.

Airlines would be charged up to £50 per person each time they landed, with reduced rates for efficiency and cleanliness.

Dr Lucas said the argument that airlines would simply fly elsewhere if such charges were introduced would fall apart if the policy was introduced across Europe.

Anti-runway stalwart Brendon Sewill, of Gatwick Area Conservation Campaign, said: "Aviation across Europe is expanding out of control because of the tax-free basis. The answer is to campaign simultaneously in each country.

"Working together in a Europe-wide scheme would give small groups like ours a bigger voice."

The deadline for submissions on the Government's development White Paper is June 30.

On Monday night, Burgess Hill Town Council backed expansion plans.

Crawley Borough Council are due to vote on this issue tonight.

The Government says up to three new runways are needed in the South-East over the next 30 years.

The first new runway is expected to open in 2011.