The Swedish manufacturer has given the green light to the Polestar Racing team to run a C30 for the introduction of new regulations next season.
Dahlgren and Polestar have made several WTCC outings in recent years, the last being at Brands Hatch this July, as groundwork for a full-time programme. The team has been pushing for support from Volvo, and has now been granted next season as a precursor to a possible full works entry the following year.
"Racing results in 2011, however important, will be second priority," said a Volvo statement."Polestar's first and foremost task is to evaluate the car and the championship to provide Volvo with a technical and commercial base to finalise an official Volvo entry from 2012."
Polestar Racing managing director Christian Dahl added: "We are very happy and proud for this vote of confidence. It will be a challenge for us but we have been prepared for this for several years. Our organisation is in place and we have already started the preparation."
The manufacturer is keen to commit to a long-term touring car programme and sees the introduction of 1.6-litre turbocharged petrol engines from next year as the perfect platform.
"Volvo has a long standing tradition in touring car racing and through the WTCC we see a potential for converting this into a global commercial tool from 2012," said board chairman Magnus Jonsson. "It is vital that technical and commercial aspects of the series align with our ambitions, and this is what Polestar will answer for us in 2011."
WTCC promoter Marcello Lotti welcomed the addition of a fourth manufacturer for 2011, joining BMW, Chevrolet and SEAT.
"It is with the greatest satisfaction that we welcome Volvo's participation in the 2011 WTCC," he said. "They supported us back in 2002 when we launched the FIA S2000 class in the European Touring Car Championship, and now they are back again the moment we adopt new technical rules, which shows their trust in the FIA and our organisation.
"To have such an important brand backing WTCC in these difficult times for motorsport is a big boost for all of us, and I am confident that Volvo's move will have a positive impact on those car manufacturers that have showed interest in joining the championship."
Dahlgren and Polestar will attempt to seal the Swedish Touring Car title at Mantorp Park this weekend, and will also contest the WTCC round at Okayama on October 31.
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