France should rein in tax policies favoring diesel engines after a World Health Organisation review found a clear link between their exhaust emissions and cancer, the country's environment minister said.
The French auto market, which was 72 percent diesel last year, should reduce its dependence on the fuel, Nicole Bricq told reporters on the sidelines of a conference in Paris on Wednesday.
"The national vehicle fleet is completely unbalanced," said Bricq, who took office last month following the election of Socialist President Francois Hollande.
Tax policies had encouraged this imbalance and should now be adjusted, Bricq said.
"I'm in favor, and the competent ministers will have to be convinced," she said. "This study comes at an opportune moment for us to make changes."
European countries have favored diesel partly because cars using it are more fuel-efficient than similar gasoline-powered vehicles and emit less carbon dioxide.
Bricq was speaking a day after the WHO's cancer research agency said its review of all relevant published science had removed earlier doubts about the carcinogenic effects of diesel exhaust.
France levies a tax of 43 euro cents per liter on diesel and 61 cents on petrol, according to industry data for 2011, leading to a similar difference in prices at the pump.
The country's main automakers, PSA Peugeot Citroen and Renault are among the most reliant on diesel sales in their home market and the rest of Europe, analysts say.
Peugeot said it was still waiting for a full copy of the WHO findings before responding. Since 2010, all its vehicles have been equipped with filters that leave no detectable trace of cancer-causing particles or benzopyrene molecules in their exhaust, spokesman Jean-Baptiste Mounier said.
Renault declined to comment, but other automakers and industry bodies have attacked the findings.
"We're convinced that this blanket judgment is completely unjustified for modern diesels," said Eckehart Rotter, a spokesman for Germany's VDA car manufacturing association.
Volkswagen, the biggest European automaker by deliveries, and which is currently seeking to increase its U.S. diesel sales, said the study "does not reflect the diesel technology that has been on the market since 2004".
The WHO cancer agency, which had first classified diesel exhaust as "probably carcinogenic to humans" in 1988, said on Tuesday it had removed the "probably" from that rating on the basis of its review.
The rating on petrol exhaust was also reviewed and left unchanged as "possibly carcinogenic", two risk categories below diesel.