Better driving, improved roads and measures such as more rational loading of freight can lower the environmental impact of trucks, European industry leaders said on Tuesday, as they pushed back against EU regulations to curb emissions.

　　Erik Jonnaert, secretary general of the European Automobile Manufacturers Association (ACEA), said he accepted the need for emissions targets.

　　But he said the industry supported market forces and "an integrated approach." As only around 10 percent of the European vehicle fleet is new, it is crucial to focus on the older 90 percent, he told reporters in Brussels.

　　He also said there was a danger of a "proliferation of targets" and Europe had gone from being one of the most profitable vehicle-manufacturing regions in 2007 to the least profitable by 2012, partly because of tougher environmental standards.

　　The EU has agreed to a limit on how much carbon dioxide cars can emit of 95 grams per kilometer by 2021. It was only agreed after lengthy argument and extra concessions to satisfy Germany, home to luxury car manufacturers such as BMW and Daimler.

　　Environmentalists are now pushing for tougher standards by 2025 and at least four EU governments - Finland, Ireland, the Netherlands and Sweden - also called last year for the European Commission to publish challenging new targets for 2025.

　　The industry is suggesting alternative approaches.

　　Compared with a "new vehicle only" approach, the integrated approach, including measures such as driver training, has the potential to double the annual carbon dioxide reduction rate from trucks, to up to 3.5 percent, ACEA said.

　　It commissioned a separate study by FTI Consulting that found EU environmental standards would add 16 percent to average car manufacturing costs in Europe by 2020 and that they could not be passed on to consumers.

　　ACEA's proposals on Tuesday drew criticism from environmental campaigners, who favor specific emissions targets for all kinds of vehicles and said ACEA was shifting the emphasis from the need to invest in fuel-efficient engines.

　　The campaign group Transport and Environment quoted research published this week by another consultancy, Ricardo, which showed an integrated approach was inadequate and a new 2025 target for cars and fuel efficiency technology for trucks would have far more impact on cutting greenhouse gas emissions.

　　The Volkswagen emissions scandal is primarily about nitrogen oxide, but the company has also admitted it understated carbon dioxide levels, prompting the European Commission to demand details from VW and from all 28 member states.