Dollar weakens as investors bet on end to Iran war Dollar weakens as investors bet on end to Iran war The US dollar fell against most major currencies on Wednesday as investors reacted positively to signs the US-Israeli war on Iran could move towards a resolution. The dollar index, which tracks the currency against six major peers, dropped 0.4 percent to 97.941 after earlier falling to 97.623. The index reached its lowest level since late February, before Israeli and US strikes on Iran triggered the current conflict.