The US Treasury says it will target Iran's economic partners, with a plan due to be unveiled at a press briefing on 24 Aug 2026. China buys about 90% of Iran's exported oil, so it is the main target, and Washington has so far been cautious about hitting major Chinese banks. Analysts doubt the policy will be enforced hard enough to stop trade routes. For Thai SMEs, there is no direct cost change yet. If you trade with Iran, or route payments or shipments through third countries, check your counterparties and banks now, because secondary sanctions can reach any country's firms and financial institutions.