UN Climate Change News, 9 October 2025 – Lead reviewers under the Paris Agreement's Enhanced Transparency Framework (ETF) play a crucial role in ensuring the quality and consistency of technical expert reviews of Parties’ Biennial Transparency Reports (BTRs). These reports assess the actions countries have taken to deliver on their climate commitments, and help inform decision-making, attract climate finance, and strengthen national climate policies over time.
BTRs provide key data on national greenhouse gas emissions, progress towards national climate plans (NDCs), as well as information on finance, technology transfer, and adaptation efforts, among others. Successful technical expert reviews of BTRs are essential to assessing progress on climate action and identifying where further efforts and support are needed.
The 2025 annual meeting of lead reviewers was held virtually in September, bringing together 63 experts from both developed and developing countries. Observers included the co-chairs of the Paris Agreement Implementation and Compliance Committee (PAICC).
Lead reviewers ensure the quality, objectivity, and timeliness of technical expert reviews, providing continuity and consistency across Parties. They meet annually to discuss ways to improve the efficiency and consistency of the review process.
Since July, lead reviewers have been working in groups to strengthen BTR reviews. During the September meeting, they adopted conclusions aimed at boosting the effectiveness and impact of reviews, while welcoming progress by the UNFCCC secretariat in organizing the 2024-2025 review cycle, including the rollout of simplified reviews for Annex I inventories.
Participants also agreed on guidance covering seven key review areas, including flexibility for developing countries, inventory methods, and the treatment of NDC targets and mitigation measures. The meeting underscored the importance of continued Party support – both financial and through expert nominations – to sustain the review process.
Later this month, UN Climate Change will present the first BTR synthesis report, providing an initial picture of Paris Agreement implementation. The report will highlight progress made in mitigation, adaptation, and support, while identifying areas where additional efforts are needed to achieve the Paris Agreement goals.
