The LEZ, which would be the first in the UK, is due to be introduced in 2008 and will mean commercial vehicles that do not meet strict emissions standards will have to pay up to £200 per day to enter London.

Louisa Perry, FTA's Regional Policy Manager for London said, "Industry supports the principle of improved air quality, but not at any cost. The Transport for London proposals represent very poor value for money.

"The scheme will cost, TfL predicts, around £130 million to set up and run - a cost that will have to be met by London taxpayers. But, because only 6 per cent of London traffic will be subject to this scheme, it will only deliver a tiny improvement in air quality.

"The whole scheme is supposedly based on the need to meet EU air quality targets but TfL has admitted that the LEZ will not achieve this even if cars were included.

"Commercial vehicles and coaches that do not meet the required standard (Euro III in 2008 and Euro IV in 2010) will have to pay a daily charge of up to £200 to enter the capital and failure to pay will result in a penalty charge in the region of £1,000.

"On the other hand operators could buy a new lorry costing anything up to £100,000!

"FTA also has serious concerns regarding the enforcement regime, which depends on automatic number plate recognition by camera being matched against existing records - which may or may not be accurate.

"The TfL scheme would automatically assume the vast majority of vehicles are compliant if registered by a certain date - whether or not that emissions standard has been maintained throughout the life of the vehicle.

"There will be no roadside testing to detect actual emissions and as such it is virtually impossible to predict how air quality might improve year on year.

"Vehicle manufacturers have reduced engine emissions massively in recent years and all vehicles are subject to an annual emission test.

"There can be no doubt that the days of lorries belching black smoke are long since over, but this scheme does little to encourage operators to take on the very latest technology, as early as possible, because it provides no incentives such as a reduction in the daily congestion charge or the ability to operate at night.

"FTA is working with a group of interested organisations in order to establish the true cost to industry and London businesses and we will continue to engage with TfL in order to help design a scheme which will deliver genuine air quality benefits."