Opel is set to take on Mini's Cooper and Fiat’s 500 with an all-new hatchback. Our spies spotted the new model, designated Junior, undergoing testing. The new model snapped up in our spy images shows what is said to be a 3.7 metre-long, two-door hatchback based on a shortened Corsa platform. Though heavily disguised, judging by the images, the new model appears to borrow elements from Toyota's Auris, Hyundai's i30 and even Nissan's Tiida. It does not, however, appear to bear much resemblance to its Corsa or Astra siblings.Nick Reilly, General Motors Europe president, described the Junior as “low cost” and expects the new model is set to bolster the German automaker’s small car range.'STYLISH MINICAR'Reilly said, “It’s a chic and stylish minicar that fits with today’s hip, urban spirit. It is not a low-cost verison of the Corsa.” GM Europe is investing R113bn in new models and powertrains over the next three years. A new petrol engine is under development for the Junior while GM has confirmed its baby hatch will also sport a battery-electric version.Production of Junior will begin at the Eisenach plant in Germany, late in 2012, with the new model going on sale in 2013.Check out our gallery!