GM Ponders a Buick Mini

General Motors Co. says it might develop a Buick version of its Opel Adam city car for the American market but not until the just-introduced European minicar gets a major overhaul perhaps four years from now.

The Adam, which sells for $15,300 in Europe, is about the size of a Fiat 500. The highly customizable three-door hatch was unveiled at the Paris auto show last autumn and went into production in Germany in January.

Opel Chairman Karl-Thomas Neumann adds that GM hopes to integrate Buick and Opel product development in the future. But he says the Adam wasn't designed for U.S. safety regulations and cannot be economically modified in its current form.

CEO Dan Akerson floated the notion in June of an Adam variant for Buick. Other GM executives repeated the idea to reporters on Tuesday during the Frankfurt auto show. They also indicated the option won't be viable until the Adam completes an extensive engineering update.