Climate policy today is no longer a purely environmental issue; it has become a field in which trade tensions, industrial strategies and great power competition intersect. The multilateral climate regime built on consensus and negotiation over the course from Rio to Paris is therefore increasingly confronted with unilateral regulatory instruments.
At the centre of this transformation stands the EU, which has shifted its climate leadership from normative discourse to a regulatory programme. The 2019 European Green Deal, by placing climate policy at the core of the Union’s growth, industrial and foreign policy strategies, has over time turned it into an instrument of external influence. The most concrete example of this instrument is the Carbon Border Adjustment Mechanism (CBAM), which entered its definitive phase on 1 January 2026. By applying to imported goods a carbon price indexed to the EU ETS, the mechanism effectively converts the Union’s internal climate standard into a trade and foreign policy tool.
The central argument of this analysis is that the principal problem CBAM creates is not its economic cost but the ambiguity of its relationship with the multilateral regime. While the mechanism derives its legitimacy from the Paris Agreement, its scope and implementation criteria are determined entirely within the EU’s own institutional processes. Türkiye is one of the important cases in which the consequences of this ambiguity can be observed. Affected only to a limited extent under the current scope, it would become the most exposed trading partner in the event of an extension. COP31, to be convened in Antalya, thus gains significance for the institutional opportunity it offers to bring questions of scope and common methodology onto a multilateral footing through the trade dialogues established in Belém.
