European Union lawmakers have demanded that carmakers cut average carbon dioxide (CO2) emissions levels by 40 percent between 2007 and 2021, a goal that has become harder to attain after WLTP emissions tests were introduced in 2018.

Carmakers including Daimler are now struggling to lower their average emissions of carbon dioxide by 2021.

"We have not finalised and published the 2018 number but it is fair to say it is an increase which makes the gap to 2021 even bigger," Zetsche told analysts during a presentation of 2018 earnings results.

To compensate higher emissions readings, Daimler, which owns the Mercedes-Benz and Smart brands, will push sales of electric and hybrid vehicles, Zetsche said.

(Reporting by Edward Taylor; editing by Thomas Seythal)