The video, which was posted in unlisted form on YouTube in the middle of April, was discovered overnight by Carscoops. Reports indicate that the Levorg STI will be launched in Japan around the middle of 2016.
It's unclear whether the Levorg STI will be made for export.
Under the hood, the Levorg STI could feature the 227kW/422Nm 2.0-litre turbocharged four-cylinder boxer engine that's used in the Japanese domestic market version of the WRX STI. The company's signature symmetrical all-wheel drive system is a given.
In Japan, the most powerful Levorg currently on sale, the 2.0GT-S, has a 221kW/400Nm 2.0-litre turbo.
If the prototype seen in the video is any guide, the Levorg STI will be fitted with Bilstein shocks, 19-inch alloy wheels, a flat-bottomed leather steering wheel, and purple and dark grey leather seats. The development vehicle also seems to be fitted with a CVT.