Swiss Franc Weakens as Fading US-Iran Deal Hopes Lift the US Dollar

On June 1, 2026 the Swiss franc weakened as fading hopes for a US‑Iran diplomatic deal pushed investors into the US dollar. The US Dollar Index (DXY) climbed in European trading and USD/CHF rose sharply, breaking above recent resistance as traders favored the greenback amid renewed geopolitical uncertainty. The move reflects a broad repositioning in FX markets rather than Swiss‑domestic drivers, with safe‑haven flows benefiting the dollar over the franc. The situation highlights how shifts in diplomatic prospects can quickly reallocate risk and safe‑haven demand across currencies, leaving USD/CHF sensitive to further developments in US‑Iran negotiations or any signals from the Swiss National Bank.