Climate mitigation can only be achieved through international cooperation, due to the global externality of greenhouse gas emissions, which asks policy centralization somehow and should take into account the wideness of participation, scope and ambition of mitigation actions. Several approaches were established or designed to address the international climate mitigation cooperation, including UNFCCC,Kyoto Protocol and its Doha Amendment, Cancun Agreements, etc. These approaches take trade-off among participation, scope and ambition in different ways, however, none of them successfully addressed the issue. The Paris Agreement established a mitigation cooperation approach called "pledge and review", which could be satisfied with wide participation, full range of mitigation scope, and would partially address the matter of ambition by the transparency, compliance and global stock take mechanism as set.