An-electric version of the Chevrolet Volt will be built, to take on competitors such as the Nissan Leaf, GM vice chairman Bob Lutz has confirmed.
The standard Volt can run for up to 40 miles on a charge, before switching to a 1.4-litre engine starts up to generate electricity to power the car. It will go on sale in the US later this year, and in Europe in 2011.
Lutz told reporters at the Detroit motor show that it would be "technologically trivial" to build the all-electric version of the car.
"Once you've done the Volt, pure electric is trivial. You just leave some parts out," Lutz said.
Lutz also warned that electric vehicles may not get the full stated range on fully electric power because of weather, atmospheric conditions, terrain and driving habits.
"It varies a lot more than the range variation with a gasoline-powered car depending on your driving style," Lutz said, confirming he had got just 28 miles from a Volt during extreme cold weather.