UK engineering company Dyson, best known for its vacuum cleaners and fans, is working on a premium electric car to go on sale in 2020.

The company will spend £1 billion on the battery and £1bn on designing and making the "radical" car.

Over the past two years, Dyson has built an automotive team of 400 engineers, drawn from manufacturers including BMW, Aston Martin and Tesla, and they have been working on the secret project for the past two years at its headquarters in Malmesbury, Wiltshire.

However, the car does not yet exist, with no prototype built, and a factory site is yet to be chosen.

Sir James declined to give further details of the project. "Competition for new technology in the automotive industry is fierce and we must do everything we can to keep the specifics of our vehicle confidential," he told staff in an email.

Important points that are undecided or secret include the firm's expected annual production total, the cost of the car, or its range.

Matthew Trevaskis, head of electric vehicles at the Renewable Energy Association, said: “There’s major opportunity for UK firms, including those not traditionally associated with the automotive supply chain, to be involved in the electric vehicle industry.

“The Government can incentivise greater domestic battery and electric vehicle manufacturing by helping to make EVs the obvious new car of choice for future consumers.

"Easy and accessible charging is crucial for this, and we’re calling on Government develop a strategic charging infrastructure strategy.

“Any EV charging strategy should include the introduction of smart tariffs, three-phase power supply into new homes, ubiquitous access to charging where we live, work and play, and the incorporation of renewable power and energy storage systems to reduce grid stress.

“It’s excellent to see new companies entering the space, creating new competition, and driving fresh innovation in the sector.

"Having already acquiring Sakti3, a solid state battery company, and being well-versed in developing electric motors, albeit on a smaller scale, Dyson may have the majority of the building blocks in place to be a real contender in the electric vehicle market.”