LYON—After meeting in Toulouse over Feb. 3-4, the EU’s 27 transport ministers have now issued a declaration that they hope sets the stage for a long-term aspirational goal (LTAG) on aviation sustainability to be adopted at the ICAO Assembly in September.

The “Toulouse declaration on future sustainability and decarbonization of aviation” was signed by 42 states. The most prominent non-EU countries include the U.S., the UK, Canada and Morocco.

France has taken on the presidency of the EU for six months and Jean-Baptiste Djebbari, the country’s transport minister, is betting on a snowballing effect to garner more support. Unanimity will be required for the LTAG to be agreed, he notes. ICAO’s triennial assembly gathers 193 member states.

The LTAG is far from being a done deal. Some countries have been reluctant, officials at the ministry say. What are the chances of seeing the LTAG adopted in September? “We know we will have to talk to some key states [such as] Brazil, India and South Africa, as well the various players in the Middle East,” Djebbari answers. “The idea is to arrive at ICAO’s assembly as well equipped and convincing as possible, to take everyone on board.”

“We also have the EU-Africa summit happening in the next two weeks,” adds European Commissioner for Transport Adina Valean.

The diplomatic endeavor, while a long-drawn-out job, is deemed necessary for the industry to benefit from consistent support globally. “If we want to meet the objectives and meet them in a fair way on a level playing field and ruling out circumvention strategies, we have to lay the foundations at an international level,” says Djebbari. “Since 2016, we have an offset tool [the Carbon Offsetting and Reduction Scheme for International Aviation, known as CORSIA] that is set to grow, and we have tried to structure the ... Declaration of Toulouse in connection with it.”

The declaration is a non-binding joint statement by the signatories. It essentially reaffirms the need—and countries’ existing commitments—to reach net-zero carbon emissions by 2050. The document says that reaching that goal may include aircraft technology progress, improved operations, the use of sustainable aviation fuels, market-based measures, and financial incentives. It also notes that non-CO2 environmental impacts have to be addressed.

The social dimension of the sustainability concept is also mentioned, as “adequate social dialogue [should be] conducted at all stages.”