The ten-year boom in four-wheel-drive off-road vehicles has gone into reverse for the first time.

Sales dipped 1,536 units, or 1.4 per cent, to 105,196 in the first seven months of the year compared with 106,732 in the same period last year.

Ken Hurst, editorial director of The Manufacturer magazine, who has been monitoring the figures, said there were a number of reasons.

"Sales have been constantly rising for years and this is the first dip," he said. "Obviously petrol prices have gone up and it could be off-roader owners have been put off by talk of large rises in vehicle excise duty.

"It may be 4x4s are going out of fashion. Possibly children who once saw the vehicles as status symbols now feel ashamed when they are dropped at the school gates."

According to Mr Hurst's figures, just 78,000 new 4x4s were sold in the UK in 1996.

By 2005 this figure had risen to more than 187,000, with market leader Land Rover, based at Solihull, enjoying its highest ever annual sales.

While that was good news for the West Midland automotive industry, not everyone has been celebrating.

Greenpeace protesters invaded the Lode Lane factory last May and shackled themselves to assembly lines.

And Mayor of London, Ken Livingstone, has proposed charging 4x4 owners £25 a day for the London congestion charge rather than £8.

The House of Commons Environmental Audit Committee recently recommended an annual vehicle excise duty of £1,800 for off-roaders - about nine times the current level.

Emily Armistead, of Greenpeace, said: "The most polluting vehicles, like many makes of 4x4, are spewing huge quantities of greenhouse gas into the atmosphere causing climate change.

"It's encouraging that sales of 4x4s have slowed for the first time. It shows Britain may at last be turning its back on climate-wrecking cars as scientists warn that global warming poses a huge threat to the planet.

"But tens of thousands of urban 4x4s are still sold every year in Britain. Tony Blair should enact proposals from backbench MPs to tax these polluting vehicles more heavily so they are driven off our roads completely."

Land Rover, which employs 10,000 people and supports a further 50,000 supply chain jobs, says each new model it introduces has lower emission levels than its predecessor.

The company recently launched a C02 offset programme under which customers will pay up to £160 per car extra to help finance a range of eco-friendly projects.

Emissions from the Lode Lane factory have been cut by 30 per cent since 1997.

The Society of Motor Manufacturers and Traders said 4x4s sales fell by only 0.1 per cent in the first six months compared with a fall of 4.2 per cent in the new car market overall.