The International Civil Aviation Organisation (ICAO), which holds an assembly every three years, set out a major climate initiative at its last full gathering in 2016, but aviation leaders are under pressure to do more after overall carbon emissions hit record highs last year.
Reuters Newsagency reports the plan, known as the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and the first of its kind for a single industry, is a medium-term scheme to help airlines avoid adding to their net emissions from 2020.
Airlines, which are facing public protests over the issue, have urged ICAO to commit now to setting longer-term goals to reduce emissions at its 2022 assembly.
“It is possible at the same time to fly and to reduce our carbon footprint,” said International Air Transport Association (IATA) director general Alexandre de Juniac, on a conference call with reporters.
“Flying is not the enemy.”
Reuters reports Ms Thunberg, the teenage climate activist who admonished world leaders at the UN General Assembly in New York for failing to protect the environment, will lead a street protest in Montreal on Friday.
Commercial flying accounts for 2.5 per cent of carbon emissions.
With passenger numbers forecast to double to 8.2 billion by 2037, experts say emissions will rise if no action is taken.
The United States, which intends to quit the UN sponsored Paris Agreement on climate change, backs the UN-negotiated CORSIA, which is supported by most airlines and would cap rising aviation emissions at 2020 levels through the purchase of carbon offsets.
However, US support is tied to other major aviation countries also backing the plan and a guarantee that CORSIA would prevent airlines from being subjected to separate and more costly carbon tax schemes by individual countries, a US State Department official said.
Reuters reports Europe, meanwhile, wants to keep its right to run separate emissions schemes.
“We support CORSIA being a first step, a minimum at this stage,” said Pascal Canfin, chair of the environment committee of the European Parliament.
“But we believe our sovereignty allows us to be more ambitious if we wish to be so, and this is something that all ICAO members should respect,” Mr Canfin said.
Allowing other offsetting programs would put a “double charge” on airlines and could weaken other countries’ resolve to participate in CORSIA, Mr de Juniac said.
He added that he did not believe Europe’s actions would put US resolve for the deal at risk.
ICAO cannot impose regulations but sets standards that are approved by its 193 member countries.