LIBERAL Democrat leader Nick Clegg chose Chippenham to today unveil a £100 million prize fund for green car manufacturers.

The prize is for a manufacturer producing an ultra-low emission vehicle that becomes a top five selling car within a year.

Mr Clegg hopes the incentive will help make Britain a world leader in low emission vehicles. He said it would both stimulate the economy and help the environment, which would in turn improve people’s health.

He made his announcement during a visit to wheel manufacturer Dymag, based on Bumpers Farm industrial estate. It has just been promised a government grant and loan package of £7.1 million to help it mass produce its carbon composite wheels, whose ultra-light weight helps reduce fuel consumption.

Mr Clegg said the prize fund and the support for research and development were part of a bold ambition to have all cars on UK roads ultra-low emission from 2040 onwards.

While at Dymag he handled the wheels and appeared very surprised by the differences in weight.

He said companies like Dymag, whose product works to cut emissions, would do very well in the future.

“I want Britain to be a green country," he said.

"This isn't just about re-balancing the economy, it's also about tackling dangerous levels of air pollution that reduce average life expectancy by up to eight months.

“Our Liberal Democrat £100m prize fund will spark a low emission car revolution in Britain and help to build a stronger and greener economy for years to come.”

After his tour of the wheel manufacturer he joked about the emerging non-dom row, saying, “The wheels are starting to come off Labour's announcement because it turns out it isn't actually a ban".

Labour has said that in government it would abolish the non-domicile rule that allows some wealthy UK residents to limit the tax paid on earnings outside the country.

Ed Miliband said the non-dom rules were "indefensible" in the 21st century and made Britain "an offshore tax haven". Shadow Chancellor Ed Balls said today the move could raise "hundreds of millions of pounds".

Mr Clegg said: "We've got to get the balance right as a country, we’ve got to be open for business but not open for abuse. Labour has lost sight of that.

“When it comes to taxation it has always been the Lib Dems that have had to take the lead to make sure people at the top pay their fair share.

"I am so dismayed that the Conservatives want to depart so radically from that and for the first time in years don’t want to ask the wealthy to pay a single penny extra.”

He reiterated his "consistent" support for remaining in the European Union, saying his position had not wavered over the years, whereas he "cannot keep up with Cameron’s promises" on the issue.

Speaking to reporters in London about her role in the campaign, Mr Clegg's wife Ms Miriam Gonzalez Durantez said: "I keep my day to day life, I keep working, I'm doing what I did last time which is to help as much as I can.

"I have seen Nick and these guys for five years putting country above party consistently, every single day.

"Very often at a great personal cost - they deserve to be back."

However, polling indicates Mr Clegg faces a tough battle to hold his own Sheffield Hallam seat.

The Deputy Prime Minister has been behind in constituency polls and faces being punished by the electorate for his role in the coalition government.