The European Union's executive arm approved plans on Wednesday (December 20), to include aviation in its emissions trading system, giving international flights in and out of the EU a one-year reprieve before they have to join. Intra-EU flights will join the scheme, aimed at cutting global air pollution, in 2011. Flights into and out of the bloc will follow the next year, the European Commission said. The quotas allowed for carriers will be equal to the average 2004-2006 emissions data. "EU emissions from international air transport are increasing faster than from any other sector. This growth threatens to undermine the EU's progress in cutting overall greenhouse gas emissions," the Commission said in a statement. The EU emissions trading scheme -- its key tool to battle global warming and meet Kyoto Protocol emissions reduction targets -- puts a limit on the amount of carbon dioxide (CO2) big polluters such as power plants and oil refineries can emit. But so far it had excluded aviation, a major and growing source of pollution as air travel booms. The majority of the permits will be given away but 10 percent will be auctioned. Unlike in the current trading scheme where member states set limits subject to the Commission's approval, the EU's executive will deal with the caps itself. The original plan to include all flights from the start drew criticism from the airline industry and major trading partners, including the United States, that the draft went beyond acceptable limits and effectively regulated non-EU carriers. But Environment Commissioner Stavros Dimas said he thought the proposal was safe from any legal challenge. "Our proposal is in accordance and compatible with international law. I expect that United States airlines or other airlines will not challenge legally something that they know they are not going to win," Dimas told a briefing. The industry and carriers emphasised that they were responsible for only 1-2 percent of global emissions and that they had already done much to cut their output, such as making planes more efficient. Some airlines, such as EasyJet saw the plan as acceptable. But Lufthansa criticised the plan, saying the industry was already doing everything it could to reduce emission. The Association of European Airlines (AEA), representing big carriers such as British Airways, Air France, KLM and Lufthansa, said its members were likely to end up buying permits, rather than selling, as the cap was so strict.