The proposal, expected to be approved by the EU executive on Wednesday, aims to reduce the number of premature deaths caused by pollution in the EU from 370,000 a year to 225,000 by 2020. It would introduce tougher controls on particulate matter, or fine dust, which causes most premature deaths. But it would introduce less stringent emission ceilings for air pollutants such as nitrogen oxide, sulphur dioxide and ammonia than had been envisaged before the summer.

While recognising a “change in the level of ambition”, Stavros Dimas, the European Union's environment commissioner, argued that the proposal was testimony to Brussels' determination to stick to an ambitious environmental agenda. Following July's meeting of the Group of Eight leading industrial nation in Gleneagles, which was largely devoted to climate change, the EU is also keen to maintain its profile as the leading force behind the Kyoto Protocol and initiatives to lower pollution levels.

Mr Dimas said: “Whatever way you look at it, the benefits of clean air far outweigh the costs. Nobody is immune from air pollution and I am sure that industrialists, who also breathe the same air, must be pleased.”

Air pollution is one of seven areas that are seen as a credibility test for Mr Dimas, a former Wall Street lawyer whose appointment was greeted with scepticism by environmental groups. Separately, Mr Dimas is also preparing to tackle the environmental impact of the aviation sector with a proposal to include aviation in the EU's carbon dioxide emissions trading scheme.