The Geneva motor show star will be the fastest and most powerful production Astra road car made by the manufacturer so far.
The Extreme is based on the 2013 Opel Astra Cup race car and features a host of race-bred modifications, including racing seats, six-point harnesses, aerodynamic upgrades and the extensive use of carbonfibre.
Astra Cup racers also feature carbonfibre doors and a carbonfibre bonnet, which could feature in the new Vauxhall Astra VXR Extreme.
Other changes for the Extreme include the addition of a more aggressive-looking quad-exit exhaust system, compared to the standard car's twin-exit system, new bumpers, a large fixed rear wing and bespoke wheels and tyres.
No technical specifications of the Astra VXR Extreme have been announced ahead of its Geneva reveal in March but it's thought the car will offer more than 300bhp, compared to the normal VXR's 276bhp.
Standard VXRs utilise a 2.0-litre turbocharged direct-injection engine that produces 276bhp at 5300rpm and 295 lb ft at 2400-4800rpm, allowing for 0-60mph in 5.9sec and a top speed of 155mph.
The Astra Cup cars produce a higher 296bhp at 5600rpm and a similar amount of torque, however, with their additional weight reduction further improving their performance.
The launch of the Vauxhall Astra VXR Extreme concept, which will be the basis for a future low-volume production model, will coincide with the tenth anniversary of the VXR brand.
Pricing is yet to be announced but expect the Extreme to command a significant premium over the the standard Astra VXR, which costs £27,260.