Carbon dioxide rather than NOx is “the biggest issue” of combustion engines, and customers are showing more confidence in diesel than politicians by continuing to buy them in significant numbers, according to Mercedes boss Dieter Zetsche.

Highlighting that the firm sold more diesels in Europe in 2017 than in 2016 and that diesels are crucial to reducing the amount of CO2 put into the atmosphere, Zetsche said: “I do believe it is not to the benefit of society to turn down the benefits of CO2 savings that diesels offer. We are talking a lot about NOX but I believe CO2 is still the biggest issue.

 Diesel cars produce more NOx than petrol cars, but less CO2

“In 2018 we are seeing a small dip in diesel take-up, but customers, on the whole, are still showing confidence. More than 50% of our sales are diesels. They are more open to the options than the political discussions suggest.”

Despite this, Mercedes is investigating voluntarily introducing its own economy and emissions bandings to help drivers understand the effects of different types of driving and roads. “The new regulations and test methods are a great step forward, but if we can offer even more realistic information that helps the customer then it can only be a good thing,” he said.