Smart Fortwo teased in mock ads ahead of July 16 debut

The videos - which are supposed to be funny, rather than actually giving much away about the new Smart models - indicate the anticipated growth inside the cabin of the new city car. The fresh two-door model is expected to measure almost identical to the car it replaces at 2.69 metres long, while the four-door model will stretch to 3.50m.

The new Fortwo and Forfour models have been jointly developed with Renault, and are based on the same underpinnings as the recently revealed Twingo from the French brand. The cars are rear-engined and rear-wheel drive. Powertrains include a 51kW naturally aspirated 1.0-litre three-cylinder and a 66kW turbocharged 0.9-litre three-cylinder, both of which are shared with Renault. An EV model from Smart is expected to give the German brand a point of differentiation.

Smart is under something of a cloud of uncertainty in Australia. A recent report from Australian industry journal GoAuto stated that Mercedes-Benz's local arm may not bring the new Smart models if the brand can't make money on the cars.

Smart has never hit any great heights in Australia, particularly as buyers could otherwise choose larger, more practical hatchback models for similar money. The existing Smart Fortwo is still available, priced at $18,990 driveaway for the hard-top and $20,990 driveaway for the rag-top convertible model, but the company has only managed to sell 38 examples so far in 2014.

Stay tuned for more news on the Smart brand in Australia, and the reveal of the new Smart models on July 16 (July 17 in Australia).