As the company builds towards the official unveiling of its first fully-electric plug-in car, the Ioniq, Hyundai has released some new teaser images that show the vehicle will be focused on aesthetics as much as emissions and has also confirmed it has a license for testing its autonomous driving technology on U.S. roads.

Adopting the strong coupe lines but over a sedan form - a design popularized by premium German car makers Mercedes and Audi - the Ioniq, according to its makers, will combine good looks with "class-leading" aerodynamic performance.

There are very few cars in the plug-in electric class, meaning that Hyundai's boasts could be easy to make, but what will really make this car stand out when it takes its maiden bow in Korea in January is that it will be a world first.

The Ioniq is the first vehicle that can be specified as a hybrid, a plug-in hybrid or fully electric car. Just like traditional cars can be specified with a range of different petrol or diesel engines, the Ioniq will offer owners different levels of green, but without having to change the styling or any other aspect of the car to accommodate the vastly different powertrains.

Rather than simply a demonstration of ingenious component packaging, this trick means that unlike the Toyota Prius, which wears its hybrid credentials on its sleeve, the Ioniq is bound to appeal to discerning, stealthier drivers, who simply want to reduce their carbon footprint, rather than make a bold automotive statement simultaneously.

Inside, the cabin will be dressed in eco-friendly materials and clutter cut to a minimum, something the company is convinced will appeal to the next generation of motorists.

As well as charging into the electric car market, the Korean carmaker and its sister company, Kia, are also investing heavily in autonomous driving technology. On Monday, the companies secured a license to conduct self-driving car tests on public roads, in real-world conditions, in the US state of Nevada.

Dr. Tae-Won Lim, Vice President of Central Advanced Research and Engineering Institute of Hyundai Motor Group, said: "Thanks to this licence we will be able to accelerate the testing of our new autonomous driving technologies that are currently in the early stages of development, with particular emphasis on our alternative powertrain vehicles. We are confident that our latest innovations will ultimately make driving safer for all road users."

Kia and Hyundai are aiming to bring their first semi-autonomous features to their ranges by 2020 and to be offering fully autonomous cars by 2030.