The European Parliament backed plans Tuesday to include all airlines flying within or into the European Union in the 27-nation bloc's plan to cut greenhouse gases.
The carriers will have until 2011 to join its cap-and-trade emissions program.
Under the proposal — criticized by the United States and some other non-EU countries — airlines would trade pollution allowances, forcing them to buy more credits or reduce the emissions of each aircraft if they want to fly more.
Each airline would be allowed to emit 90 percent of its average emissions for 2004-2006 for free before having to buy additional credits.
EU lawmakers tightened the draft rules so that all airlines would be subject to the rules in 2011. The original proposal, put forward by the EU's executive Commission in December, had allowed a one-year grace period for non-EU airlines.
"If one part of the sector joined the plan later, we would have competitive disadvantages," said Peter Liese, the German conservative lawmaker charged with steering the legislation through the assembly.
EU governments are expected to put the finishing touches to the proposal in the first half of 2008, the parliament said.
Opponents argue that regional steps cannot solve a global problem, and that including airlines in the emissions cap-and-trade plan would considerably increase ticket prices as airlines would have to invest in new technologies.
The United States has warned the EU risks a trade fight if it implements the plan. It has said the EU has no right to force airlines flying into the EU to participate in its program, and that it is the International Civil Aviation Organization — a U.N. body — that has jurisdiction over the matter.
But Liese said the EU had a "very sound" legal basis for its plan, and that it was prepared to modify it for any third country that came up with an equally environmentally friendly proposal for its own aviation sector.
The International Air Transport Association, which represents the airline industry worldwide, called the plan "hypocritical" and said the cost of fuel alone — making up 28 percent of airlines' operating costs — is enough to force them to reduce fuel consumption and CO2 emissions.
"Europe's go-it-alone approach on emissions trading is counterproductive. Regional schemes will have, at best, limited impact on the environment. And their unilateral application to foreign airlines is a clear breach" of international rules, IATA said.
The aviation plan is part of the EU's push to cut greenhouse gas emissions by 20 percent by the year 2020, a first step in a strategy to fight global warming and reduce Europe's dependence on oil and gas imports. Greenhouse gas emissions from aviation increased by 87 percent in the EU from 1990-2003.
Environmental groups criticized the cap-and-trade plan as inadequate.
"The European Parliament missed the opportunity to really curb the emissions of the fastest growing sector in Europe in terms of greenhouse gases," said Delia Villagrasa, senior adviser at WWF, an environmental group.
The trading system sets caps on carbon emissions by energy-intensive industries. Companies that stay below these limits can sell some of their unused quota for carbon pollution, in the form of carbon credits, to companies that have overshot their limits.
The system is meant to provide a financial incentive for cutting down on emissions. In theory, the stricter the limits on the carbon emissions, the more expensive polluting becomes.