Separately, Greenpeace claimed an important propaganda victory when a senior oil industry executive conceded it had a point in querying new oil exploration when greenhouse gas emissions from existing reserves might already be contributing to global warming.

Mr Heinz Rothermund, managing director of Shell UK Exploration and Production, said in a speech last night Greenpeace's crusade against developing the North Atlantic "frontier" raised a "key question". "Undoubtedly, there is a dilemma," said Mr Rothermund, whose own company is active in developing the new oil fields.

The group said that its report on subsidies revealed the "hypocrisy of European governments" in calling for action to fight climate change, believed to be linked to the consumption of fossil fuels, while spending "billions propping up its cause".