Volkswagen is working on a new minicar whose launch is viewed by officials as the most important project since the Golf hatchback replaced the Beetle in the 1970s. The car was previewed at last month’s Frankfurt Motor Show in the form of the up! minicar concept and according to a leaked document should be on the market by the end of 2010.

The document, which was made available to Automotive News Europe, revealed the carmaker’s desire to sell up to 4.16 million units over the car’s nine-year lifecycle and that an entire family of small cars will be developed.

Production is likely to kick off at Skoda’s Vrchlabi plant in the Czech Republic in September 2010 with 100,000 units expected to be sold under the VW label and an equal amount planned for sister brands Seat and Skoda. Officials are expecting an additional 262,000 units to be manufactured for Russia and India but these targets are said to be deliberately conservative. An inside source has revealed that VW CEO Martin Winterkorn is “setting achievable goals, since VW is venturing into new territory.”

The initial model will feature just three doors and measure 3.5m in length. The car will be priced at €8,950 and will be followed by a long wheelbase version with five doors and a price tag of €9,450. There are rumors that VW could launch even more models in the near future including an SUV variant and a plug-in electric version, which you can see a preview of by clicking here.