Cross-Border REDD+: The Evolution of African Carbon Projects

The Dja forest in Cameroon borders the Sangha in Republic of Congo and the Dzanga-Ndoki forest in the Central African Republic. Forest elephants do not recognize borders. Deforestation pressure does not either. Yet REDD+ mechanisms were designed around a national logic — each country submits its strategy, its reference data, its registry. The reality of transboundary forest landscapes creates a fundamental tension with this architecture, and the Congo Basin is its most striking illustration.

The Transboundary Leakage Problem

In REDD+ terminology, a "leakage" occurs when protecting a forested area in one country displaces deforestation pressure into an unprotected area in a neighboring country. If a project in Cameroon effectively protects a forest from illegal cutting, but loggers simply move across the border into neighboring Congo-Brazzaville, the net carbon benefit for the planet is zero — or even negative if the neighboring area was more carbon-rich.

Verra methodology VM0015, the most widely used for Central African REDD+ projects, requires developers to estimate and account for leakage in their emission reduction calculations. But estimating transboundary leakage requires data on deforestation pressures in neighboring countries — data that private developers typically cannot access directly. This is where regional coordination becomes essential.

The Sangha Trinational Model

The Sangha Trinational (TNS), a UNESCO World Heritage site at the junction of Cameroon, Central African Republic, and Republic of Congo, is the most advanced example of transboundary management of a forest ecosystem in Central Africa. With 7.5 million hectares of near-intact tropical forest, it hosts one of the continent's largest forest elephant populations and an exceptional concentration of great apes.

Joint management of the TNS, coordinated by COMIFAC with support from IUCN and WWF, has created an institutional framework for sharing deforestation data, harmonizing protection rules, and coordinating surveillance missions among forest rangers from the three countries. This is exactly the type of governance infrastructure that transboundary REDD+ projects need.

The Challenges of Multi-Country Carbon Accounting

A carbon project spanning two countries raises non-trivial accounting questions. Which country receives the carbon credits? If both, in what proportion? How are Article 6 corresponding adjustments allocated? Which national registry hosts the credits — or is a regional registry needed?

These questions do not yet have standard answers in current REDD+ rules. Verra published guidance in 2023 on jurisdictional projects (JNR — Jurisdictional and Nested REDD+) that allows private projects to be nested within broader national frameworks. But the transboundary JNR framework — one that crosses a national border — remains uncharted territory in terms of methodology.

Ongoing Initiatives

Several recent developments could advance the issue. First, the CAFI initiative (Central African Forest Initiative), funded notably by Norway, the European Union, and the United Kingdom, finances national REDD+ programs in several COMIFAC member countries. Discussions are underway to harmonize reference data across CAFI countries, which would facilitate transboundary leakage calculations.

Second, the Z3D Programme (Zero Deforestation and Degradation for Development), signed between France and DRC in July 2026 under the Belém commitments, includes mechanisms for coordination with neighboring Congo Basin countries — an architecture that could serve as a model for other bilateral or multilateral carbon finance agreements at the landscape scale.

Third, the ongoing work of the Article 6.4 Supervisory Body on landscape methodologies could eventually create a standardized framework for projects spanning multiple jurisdictions — a regulatory innovation eagerly awaited by developers working in the Congo Basin.

Cameroon's Position

Cameroon occupies a strategic position in this debate. As a COMIFAC member state with the Secretariat based in Yaoundé, it shares forested borders with five other Congo Basin countries. Its national REDD+ strategy explicitly recognizes transboundary issues and identifies the TNS as a priority zone for a coordinated management approach.

For investors considering projects in Cameroon's border forest zones, it is crucial to verify that the project PDD accounts for transboundary deforestation pressures in its reference scenario, and that leakage estimates are documented and conservative. A project that ignores deforestation dynamics in neighboring border areas takes on significant carbon integrity risk during future verifications.

The resolution of transboundary accounting questions is not imminent. But the forest landscapes themselves do not wait.