The owner of Aer Lingus says it wants to be a carbon neutral company by 2050.
International Airlines Group (IAG) says it is "stepping up" its commitment with a package of new measures.
One of these will be a cabin waste reduction plan to be rolled-out at Aer Lingus in 2020.
The programme, called Flightpath Net Zero, would see IAG be the first airline group worldwide to commit to achieve net zero carbon emissions by 2050.
This would also be in line with United Nations' objective to limit global warming to 1.5 degrees.
It is also setting three new climate targets for 2025, 2030 and finally 2050.
Its short-term target is to achieve a 10% reduction in Co2 per passenger kilometre by 2025: this means its fuel efficiency will improve from 87.3g of Co2 per passenger kilometre in 2020 to 80g by 2025.
To meet the 2025 target, IAG says it will be investing in 142 new aircraft over the next five years, which are up to 25% more fuel efficient than the aircraft they replace.
IAG says: "We are under no illusions, the challenge ahead is great. Aviation brings great benefits and 80% of emissions are for journeys over 1,500kms where there are no reasonable alternatives to flying.
"As an industry, we are currently reliant on fossil fuels and the low carbon solutions for aviation are more complex than for many other sectors. But we believe our ambitious goal is achievable.
"With Flightpath Net Zero, we are putting environmental sustainability at the heart of our business, ready to meet the task ahead.
"We are also using our influence to encourage industry partners to play their part and calling on governments to create the policies and incentives that will ensure we collectively meet our global climate goals."
It adds that British Airways, which is one of its companies, will offset carbon emissions for all its UK domestic flights - making them net zero carbon from 2020.
But the company warns that it cannot succeed alone.
It is calling on governments to support a long term climate goal for aviation via the United Nations agency ICAO, and support smart global carbon pricing for aviation - which "directly reduces climate impacts and avoids blunt taxation".
Read the full Flightpath plan here