British inventor James Dyson (www.dyson.co.uk), probably best known for revolutionising the design of the vacuum cleaner, has announced plans to build an electric car.

He said it will be “radically different” from current models and will go on sale in 2020, adding that 400 engineers in the UK had been working on the £2.5 billion project since 2015.

While no prototype has yet been built, Mr Dyson said the car’s electric motor was ready and that two different battery types were being developed, adding that he had long been concerned by diesel particulate pollution; and while he had designed filters for such engines, he had concluded that electric vehicles were the best way to progress.

While the UK remained a “frontrunner” for the production base, he said: “We’ll choose the best place to make the car, and that will be wherever we make the battery. We see a large market for this car in the Far East, and we want to be near where our markets are.”

Mr Dyson’s ambition to develop a new form of battery-powered car was accidentally disclosed in a Government document last year, along with the announcement of a £1 billion investment in battery technology last year.

The recruitment of senior staff from motor manufacturers heightened industry speculation. Mr Dyson has now announced a further £1 billion for prototype design — plus £500 million for associated costs.

Research and development work on the car will continue at a new facility being built on a former WWII airfield at Hullavington (near Dyson’s headquarters in Malmesbury, Wiltshire).

Meanwhile, an off-roader modelled on Land Rover’s classic Defender could be rolling off British production lines if Jim Ratcliffe, the owner of petrochemicals giant Ineos, can win Government backing for it.

He said he would invest £600 million to begin output of his new off-roader from 2020-21, adding that he would prefer to build in Britain, “although there are cheaper alternatives in countries such as Germany, where the workforce is already trained and Ineos could use existing sites.

"We would have to build new in the UK, so to balance that playing field — you’re talking about hundreds of millions to build a facility — would need some Government support.”

Mr Ratcliffe has identified a number of potential sites on the east coast of Britain, from Scotland down to Hull. He said a decision would be made before the end of next year.