These latest photos were taken in Germany, whereas an earlier prototype was spotted in the United States.
Despite the camouflage and body cladding, it's clear that the GT has styling that's be closely related to the 2011 GT concept, complete with a long bonnet, short front overhang, and coupe-like roofline.
The new sports sedan will be positioned as a more athletic alternative to Kia's other large cars. In the US and South Korea, it will sit underneath the luxury focussed rear-wheel drive Kia K900/K9 large sedan, but above the front-wheel-drive Optima and the larger Cadenza.
Under the skin, the Kia GT will use a version of the rear-wheel-drive platform from the Genesis G80 and G90. This means that the sportiest variant will probably use the 272kW/509Nm 3.3-litre twin-turbo V6 available in the G90 and 2017 G80 Sport.
Entry-level versions will likely be powered by a naturally-aspirated V6, while a V8 model is a distinct possibility.
The new Kia GT could debut as early as this year's Paris motor show, which kicks off at the beginning of October.
Codenamed CK, the new Kia sports sedan is expected to land in Australian showrooms during the third quarter of 2017.
Damien Meredith, Kia Australia's chief operating officer, told CarAdvice that the local arm is hoping to price the CK between the Optima and the luxury car tax threshold.
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