The European Union has been one of the staunchest supporters of the Kyoto Protocol, and has taken a lead in measures to curb greenhouse gas emissions.

The bloc’s pioneering emissions trading scheme, which started on January 1 2005, was the first mandatory cap-and-trade system covering greenhouse gas emissions from industry. Nearly 11,500 industrial installations were covered by the scheme initially, and the trade in carbon permits was worth about $50bn last year, according to the World Bank.