Growth in the aviation industry could wipe out any environmental gains made by the government MPs have warned.

The increase in the number of flights could accentuate global warming and finish any hopes of the government reaching a key target, members of the environmental audit committee said.

Increases in emissions from jets were slammed as "unsustainable and unacceptable".

Their report, published on Tuesday, claimed government plans outlined in transport secretary Alistair Darling's recent green paper would mean missing the target to cut carbon dioxide emissions by 60 per cent by 2050.

The MPs also questioned the assumptions that officials used for their growth forecasts.

They claimed the environmental costs would wipe out the economic case for expansion.

Proposals under consideration by the government include a second runway at London Stansted, a third runway at Heathrow, as well as a new airport at Cliffe in Kent, which was rejected by committee chairman John Horam.

"There is enough potential in existing airports to meet future demand - if we make rather more realistic assumptions than the DfT has done," he said.

The committee highlighted one central issue of the environmental lobby that airlines do not pay any fuel levies.

"We cannot get away from the fact that airlines pay no tax on aviation fuel - whereas 80 per cent of the price motorists pay goes to the chancellor. The government needs to use a range of fiscal and other tools to decouple the growth in aviation from economic growth," Horam said.

Liberal Democrat committee member Sue Doughty went further, accusing the government of failing to understand the environmental and economiccosts of aviation.

"They have distorted the economic arguments to justify their approach to airport expansion," she said.

"The 'predict and provide' policy, on which the Department for Transport has based their consultation on the future of aviation, is now thoroughly discredited.

"We should be looking at environmentally sustainable options."