Porsche has granted the 600bhp-plus Mission E an official codename, indicating that the advanced electrically powered saloon has formally entered development.

The move follows an announcement in December last year confirming that the Tesla Model S rival had been given a production green light and was tentatively set to go on sale in 2020.

The production version of the Mission E, codename J1, has been conceived to sit on a bespoke platform designed to accommodate a lithium ion battery pack capable of providing the car with a range of more than 330 miles/528 kilometres. In combination with two electric motors, the sleek four-door promises a 0-100kph time of just 3.5sec.

The new platform is said to be separate to the structure being developed by parent company Volkswagen for its new range of electric cars, which includes a production version of the Budd-E concept concept seen last month at the Consumer Electronics Show in Las Vegas.

Heading development of the zero-emissions Porsche is Stefan Weckbach, who previously led product strategy and more recently was responsible for the development of the Boxster.

Meanwhile, officials have confirmed to Autocar UK that the upcoming facelifted 911 GTS will retain its existing naturally aspirated 3.8-litre flat six engine, rather than adopting a powered-up version of the company’s new twin-turbocharged 3.0-litre flat six.