Asian currencies tumbled Monday as U.S. and Israeli strikes on Iran sparked a global risk-off wave and sent oil prices soaring. The South Korean won led regional losses, falling over 1% as markets worried about Seoul's heavy dependence on imported energy and vulnerability to oil price shocks.

The U.S. dollar index climbed 0.2% in Asian trade, with haven demand pushing it higher earlier in the session. Oil prices surged to multi-month highs on fears of supply disruption across the Gulf and threats to shipping through the Strait of Hormuz, a critical artery for global crude flows.

MUFG analyst Michael Wan noted that currencies like the won, Indian rupee, and Philippine peso face heightened risk from sustained oil price increases due to their oil import linkages. While the Japanese yen and Chinese yuan saw modest gains amid some safe-haven demand, the Australian and New Zealand dollars recouped early losses after initially sliding on the oil shock.