Sir David King, the chief scientific adviser to British Prime Minister Tony Blair, this week warned that the increasingly popular sports utility vehicles (SUVs) and 4x4s were helping to accelerate global warming.
This puts a damper on this week's big news for off-road enthusiasts - the arrival of the cheapest 4x4 on South African shores.
King, who was born in Durban and educated at the University of the Witwatersrand before leaving the country in the 1960s, said the British government was working with its counterparts around the globe to put a price on carbon-dioxide emissions.
"The only way we can stop it is by making it expensive to put carbon dioxide into the environment," he said.
"We need to put fiscal processes in place to discourage people using SUVs," he said.
He said trading in carbon-dioxide emissions had the potential to be conducted on a global scale, and had the support of the European Union, G8 members states and partners around the world.
King, addressing a briefing organised by the British Council in Johannesburg on Monday, said off-road vehicles, such as SUVs were adding to the problem because of the amount of fuel they consumed.
"The SUVs use two to three times more fuel than a standard car.
"The government car I'm using is a hybrid vehicle which gives me 70 miles per gallon (four litres per 100km) while the SUV gives you 17 miles per gallon (17 litres per 100km). We must do all we can to discourage people from using SUVs," he said.
King said global warming due to carbon-dioxide emissions was the biggest environmental challenge of the century, adding that South Africa, like China, had enormous coal reserves and would continue using them.
The focus for South Africa therefore should be on capturing and storing carbon emissions. Already, King warned that South Africa was experiencing "very big changes" in rainfall patterns due to global warming, predicting that the impact of climate change on Africa in 30 to 40 years would be as significant as that of malaria and Aids.
King met Mosibudi Mangena, the minister of science and technology, and other government officials to inform them of the British government's plans to deal with carbon-dioxide emissions and other environmental concerns. He was in the country to promote Zero Carbon City, the British Council's awareness campaign on global warming.
Last week The Sunday Independent reported on the government's concern at damage being caused to ecosystems by off-road vehicles.
The popularity of off-road vehicles has grown in South Africa during the past decade. The market is set for further expansion with the release of the Panda, a 4x4 from Fiat, that goes on sale at R125 000 for an entry-level vehicle and less than R140 000 for the top-of-the-range model.
"The car is more eco-friendly, not a huge fuel guzzler and will not cause pollution," said Clinton Yon, the Fiat spokesperson.