Japanese equities slipped Monday morning as chip-sector weakness and escalating Middle East tensions weighed on sentiment.
The Nikkei 225 shed 495.7 points to open at 66,339.85, down 0.7%.
According to Iranian state media, US airstrikes hit Qeshm Island and multiple cities in southern Iran, including Shadegan, Sirik and Hajiabad.
In response, Tehran launched its third attack in three days against Kuwait, striking a water desalination and power facility.
Sentiment was also dampened by the recent pullback in semiconductor and AI stocks amid concerns of profit-taking and higher valuations.