Skip to main content


NAIROBI, 30 OCTOBER 2023 - Parties and other stakeholders convened for the Thirty-Fifth Meeting of the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer (MOP35) in Nairobi, Kenya, from 23 to 27 October 2023, the first MOP in more than 20 years to take place at the home of the United Nations Environment Programme. Despite a heavy agenda, the parties successfully concluded the meeting with a number of key decisions reached after rounds of lengthy negotiations.

Main issues for discussion included the replenishment of the Multilateral Fund (MLF) for 2024-2026 to support implementation of the Montreal Protocol by developing countries. At nearly US$ 1 billion, this is the highest level approved in the Fund’s history. This amount is necessary to support developing countries (also referred to as “Article 5 parties”) during a period when they continue to phase-out hydrochlorofluorocarbons (HCFCs) and start to phase down highly climate-warming hydrofluorocarbons (HFCs). The parties also agreed on the terms of reference for the 2026 quadrennial assessment by the three scientific panels to the Montreal Protocol to chart the paths for the Montreal Protocol.

Other discussions included the import and export of prohibited cooling equipment, the potential revision of the HFC baseline for some Article 5 parties as a result of COVID-19, critical-use exemption for one party requesting the continued use of small quantities of methyl bromide in agriculture where alternatives are not feasible, as well as assessing the processes for the effective implementation of the Montreal Protocol and identification of gaps in the global coverage of atmospheric monitoring of controlled substances and options for improvement. Parties also discussed and took decisions on emerging issues such as stratospheric aerosol injections (geoengineering), very short-lived substances, increasing emissions of HFCs and carbon tetrachloride that affect ozone levels.

The three assessment panels to the Montreal Protocol updated the parties on the latest information in the synthesis report of the 2022 quadrennial assessment reports by the three Assessment Panels.

The high-level segment was opened on Thursday 26 October with statements from Inger Andersen, Executive Director, United Nations Environment Programmes (UNEP) urging the parties to push for universal ratification of the Kigali Amendment to reduce HFCs, enhancing energy efficiency at the same time and thus continue to contribute to avoidance of global warming.

Soipan Tuya, Cabinet Secretary, Environment, Climate Change & Forestry of the Republic of Kenya pressed on the need for continued financial support to developing countries through the Multilateral Fund.

On the margins of the meeting a total of 22 side events and 5 exhibitions also took place, including a side event by a youth delegation keen to connect with the work of the Montreal Protocol and a presentation by the Scientific Assessment Panel on geoengineering and combined with the Technical and Economic Assessment Panel on HFC-23 – a very potent greenhouse gas – which attracted many of the delegates. The assessment panels also used the opportunity while in Nairobi to meet separately with the UNEP Executive Director to discuss concerns around emerging challenges potentially impacting ozone recovery and linkages with other processes relevant to science and assessment.

The workshop on energy efficiency to promote the transition to energy efficient and low- or zero-global-warming-potential technologies as requested by the parties was also held on 22 October and its outcomes were presented to the MOP35 for discussion.

The decision on energy efficiency requests the Technology and Economic Assessment Panel to continue to update information on energy efficient technologies and relevant information for 2024, and a decision on the life-cycle refrigerant management included a request for the Ozone Secretariat to organize a workshop on the matter in 2024 to share experiences and assess challenges.

The parties worked late into the final night of the meeting into Saturday to find consensus on many important issues. In total, the parties adopted a total of 27 decisions.

For more information, please contact:
Stephanie Haysmith, Communications & Public Information Officer, Ozone Secretariat