China has escalated its stance on Iran’s nuclear program, joining Russia in challenging Western sanctions just as the U.S. threatens 100% tariffs on Chinese exports. A joint letter from Moscow, Beijing, and Tehran to the UN Secretary-General announced the termination of UN Security Council Resolution 2231, which underpinned the 2015 JCPOA nuclear deal. The move comes after the UN reimposed sanctions on Iran over alleged violations, while Russia and China insist the resolution’s provisions expire naturally under international law. U.S. President Donald Trump has signaled readiness to escalate trade pressure, warning of tariffs and emphasizing negotiations with Xi Jinping in South Korea. The development highlights a growing geopolitical standoff, linking nuclear diplomacy with trade tensions, rare earth export controls, and U.S.-China rivalry, raising global concerns about the future of non-proliferation efforts and regional stability in the Middle East.