The International Civil Aviation Organization (ICAO) announced on Thursday that its member states had agreed to cut global aviation carbon emissions by 2035 to 2020 levels in support of efforts to keep global warming in check.

Coming after six years of negotiations, the deal includes a voluntary phase from 2021 to 2026 and becomes mandatory in 2027 for states with larger aviation industries.

Currently, some 64 countries covering about 85 percent of international aviation activity are participating in what's the world's first aviation pollution agreement, including North America and Europe. Only the world's poorest nations, small island states and countries with global passenger travel of less than 0.5 percent will be exempted.

The framework agreement is a compromise between developed nations, responsible for most greenhouse gas emissions, and emerging and developing countries such as India and China that fear tight regulation could curb their economic growth.

Presiding over ICAO's plenary session in Montreal, Canada, was Azharuddin Abdul Rahman from Malaysia. He described the agreement as an "historic deal."

Civil aviation produces about 2 percent of global carbon dioxide emissions. The agreement - officially called Carbon Offset and Reduction Scheme for International Aviation, or CORSIA - is expected to slow the growth of emissions from an industry where passenger numbers are estimated to double to 7 billion by 2034. The deal is said to cost airlines less than 2 percent of their annual revenues.

CORSIA will apply to international passenger and cargo flights as well as business jets that generate more than 10,000 tones of emissions annually.  Airlines operating such planes will have to buy carbon credits to offset growth in emissions.

At an ICAO executive meeting earlier on Thursday, both Brazil and China, which had previously expressed reservations, voiced their support, clearing the way for the deal to go through. Virtually all of the world's major airlines wanted an agreement because they feared a patchwork of national and regional legislations might have become costlier to comply with.

uhe/kd (AFP, Reuters, dpa)