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Elon Musk says the next Tesla Roadster will be a flying car

Billionaire entrepreneur Elon Musk is about to combine the efforts from his two biggest companies to tackle one of technology's greatest challenges: building a flying car.

The Tesla chief executive said on Twitter late last night that the firm's next Roadster vehicle will be able to hold itself in mid-air, as well as travel both vertically and horizontally, easily managing a quarter of a mile in less than eight seconds.

Musk, who also runs commercial rocket firm Space X, explained that the Roadster will be adapted to use a Space X cold gas thruster system to power the new mode of travel, removing use of the two rear seats in the car to make space.

In short, it could look a little something like this (but not actually this, as there's no concept art out for another Roadster at the moment).

Whether the car would arrive by 2022 as the user suggests is another matter. Musk admitted this morning that some of Tesla's more innovative technology is facing a tough reception from international regulators.

The Summon+ feature, where a user can order their car to drive towards them like an autonomous valet service in a car park, is going through final validation in the US.

However Musk said some regions may never see the feature, after "getting some regulatory pushback" from authorities.

In the US, customers registered on the early access programme will be able to test the feature within a few weeks.