When you're in the UK to open the first official Hummer dealership, and chancellor (finance minister) Gordon Brown's 2007 budget is about to hammer drivers of gas-guzzlers, you've got to expect the conversation to turn to green issues.

But GM vice-chairman global product development Bob Lutz was happy to defend the H3, the smallest of the Hummer products and now on sale in right-hand drive through Bauer Millett in Manchester.

"I don't know why we should expect a reaction from the environmental lobby," he said in a private briefing ahead of cutting the ribbon. "The H3 meets all the emissions standards in the world and gets more than 20mpg. There's always going to be a reaction but it doesn't seem to harm sales."

Lutz argued GM could "hold its head up high" when it comes to issues of fuel economy. He said the company is the world's largest producer of flex-fuel vehicles and also offers hybrid models. He pointed out that with conventional fuels the company has 30 models achieving more than 30mpg, a feat unequalled by any other manufacturer.

Lutz didn't exactly dismiss the eco-lobby but said it needed to be seen in context, adding that sales of cars like the Toyota Prius were a tiny number in relation to the whole car market. "It's an insignificant number but it's the start of a trend. I get e-mails all the time saying we should forget all that environmental stuff and leave it to Toyota. As long as gas costs two dollars a gallon [it's actually over $3 again in many parts of the United States] it's likely that people will still want cars like Hummer."

Lutz - who recently turned 75 - also revealed more news of the Chevrolet Volt concept unveiled at this year's Detroit Motor Show. "Volt is heading for production as fast as can be, and it's not a vehicle we are trying to develop in secrecy. We are having regular briefings with environmental groups on what we're doing and it's not a PR stunt to direct attention away from our other vehicles." Something else in that direction, and just as interesting, will appear at September's Frankfurt Motor Show, Lutz added.

The Volt will include new versions of components used in the EV1, GM's electric car from a decade ago. It was never sold but leased Stateside in limited numbers to celebrities and politicians. Eventually GM recalled all the cars and sent them to the crusher, leading to a rash of negative publicity about how GM didn't care for the environment.

Lutz was honest about the lessons learned. "It was not our finest hour from a PR standpoint. We had a bunch of dedicated drivers who viewed the car almost as a religious artefact. But it was using a battery technology that was a dead end so we decided to call them back in and our legal department vigorously advocated crushing them."