China publicly opposes US sanctions on Iran but Chinese state banks quietly comply to maintain access to the US dollar system. The article analyzes China's contradictory strategy: trading heavily with Iran (taking 90% of Iran's oil exports) while avoiding sanctions penalties. This tension is driving China to develop alternative payment systems like CIPS to reduce dollar-system dependency, though global adoption remains limited. For Thai SMEs, this highlights geopolitical payment-system risks and the growing multi-polar finance landscape.