Saab and Cadillac have confirmed that General Motors' premium brands are developing "very different and specific" SUV crossovers, which will reach showrooms within two years.

Saab's managing director, Jan-Ake Jonsson, revealed that the 9-4X and an un-named Cadillac will be built at a plant in Mexico for world markets, both cars aimed at the burgeoning compact SUV sector.

The Saab is likely to debut at next January's Detroit motor show, reflecting the importance of making up lost ground on Swedish rival's XC90 in North America. Both cars are due on sale on both sides of the Atlantic within two years.

Jonsson said: "It is a growing segment and our vehicle will fit, size wise, between BMW's X3 and X5. It has become important in the premium sector to have an SUV crossover, almost an emblem or a range standard-bearer, a qualifier for brand credibility."

Both Saab and Cadillac will benefit from a new 2.9-litre, twin-turbo, V6 diesel engine under development with VM Motori, which is crucial to the upscale brands' success. The engine is also destined for Cadillac's CTS and the next generation Saab 9-5.

Saab's boss said: "Although they will benefit from shared architecture, the Saab and Cadillac will be two very different vehicles in terms of looks and driving dynamics with no chance of brand confusion."

Jonsson said the expansion of Saab's range, which includes a Trollhatten-built Astra (Delta platform)-based smaller model, was part of a "five to 10-year programme" aimed at attaining premium status on a par with BMW, Mercedes and Audi.

He added: "We believe the 9-4X, which uses our advanced X or cross all-wheel-drive technology shown in the 9-3 Frankfurt show car, fits into an emerging segment with the X3 perhaps being too small and the X5 too large."

Saab's chief executive said the brand was still having "intense discussions" about the format of its smaller car, aimed at BMW's 1-series, Audi's A3 and Volvo's C30 and likely to be badged 9-1.

He said: "We have a lot of combi or coupe customers out there in the market place, The car will be practical and sporty with the intent of bringing our average car ownership age down.

"Its production at Trollhatten helps underpin the plant's role as a compact car production centre. We might get round to sports cars when we are profitable but that is many, many years away."

A Cadillac insider said: "This project reflects the mutual benefit our two brands derive from sharing resources while maintaining our respective DNAs."

Hugh Hunston