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A landmark agreement aimed at getting the global airline sector to cut carbon emissions by 2020 was approved by the general assembly of the United Nations group that oversees civil aviation.

Delegates from 184 member countries of the International Civil Aviation Organization (ICAO) ratified the agreement on Friday.

The agreement, a framework for which details have yet to be worked out, authorizes the agency to develop a global mechanism over the next three years for ratification at the next general assembly in 2016 for implementation four years later.

Among other things, it may lead to taxing airlines for their greenhouse gas emissions.

Global aviation contributes less than two percent of all carbon emissions, but the ICAO wants a plan in place to contain greenhouse emissions as the industry continues to grow, especially in the developing world.

"I am very pleased that after long and hard negotiations we finally have a global deal on aviation emissions. This is good news for the travelling public, good news for the aviation industry, but most importantly it is very good news for the planet," said European Commission vice president Siim Kallas.

ICAO Council President Roberto Kobeh Gonzalez said the agreement is a historic milestone for air transport and for the role of multilateralism in addressing global climate challenges.

The agreement excludes a European Union proposal allowing it to apply its own cap-and-trade emissions scheme to foreign airlines until the global program takes effect.

Envoys gathered in Montreal, Quebec, declined to validate the EU's plan to include international airlines in the EU emissions trading system prior to the start of the global program. Russia, Argentina and others rejected the 28-nation EU's offer to scale back the scope of its carbon curbs in exchange for a global commitment to reduce pollution.

"While we would have liked more countries to accept our regional scheme, progress was made overall," Connie Hedegaard, the EU's Climate Change Commissioner, said in a statement. "We will now factor this in when, together with the member states and the European Parliament, we decide on the way forward with the EU (Emission Trading Scheme)."

Unless rescinded, EU regulations take effect next April and would require airlines using EU airports to pay an emissions charge.

Peter Liese, the European Parliament's rapporteur for the inclusion of aviation in the EU Emission Trading Scheme, called the resolution disappointing.

"Unfortunately, we have no guarantee that the system will be introduced in 2020 and that the benefit for the environment is substantial. There are too many ifs and buts," he said.

Friday's agreement culminates ICAO's two-week general assembly meeting.

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Associated Press writer Juergen Baetz in Brussels contributed to this report.