Opponents of Europe’s emissions trading scheme (ETS) seemed to have gotten the best of a deal reached at the general assembly of the International Civil Aviation Organization (ICAO) that should lead to a global market-based mechanism (MBM) for curbing aircraft emissions by 2020. On October 4, the assembly endorsed a plan agreed late the previous day by ICAO’s executive committee calling for the arrival of a detailed plan for the cap-and-trade MBM at the UN body’s next general assembly ahead of full implementation in 2020. However, ICAO delegates also voted 97-39 to limit the ability of the European Union (EU) to keep applying its ETS to non-EU carriers before the global plan takes effect. As of press time, details of what form such limits might take remained unclear and European Commission leaders hadn’t issued a statement clarifying whether the provisional agreement on the MBM met the conditions under which they agreed last year to suspend the application of ETS to all stages of flights to and from EU airspace, as well as within its airspace.

Under the ICAO agreement, the organization’s 36-nation Council has assumed responsibility for drafting a proposed global MBM based on a somewhat loose set of guidelines contained in the annex of Working Paper 430. One specific requirement calls for member states that implement their own MBMs before the introduction of a global MBM to exempt routes to and from developing world states whose share of international civil aviation activities accounts for less than 1 percent of total revenue ton kilometers. For now, that requirement could apply only to the EU ETS because it remains the only existing MBM. The agreement also urges, but does not require, ICAO member states to prepare action plans for reducing carbon-dioxide emissions from aircraft by the end of June 2015.

The Environmental Defense Fund commended ICAO for agreeing to progress toward a global MBM in 2020, but it warned that its success depends on leading opponents of ETS, most notably the U.S., showing leadership in implementing the plan. The group criticized ICAO for restricting the ability of member states (including the 28 EU nations) to implement their own MBMs in the meantime.