Japanese shares edged lower Wednesday as escalating Middle East hostilities pushed Brent crude toward $100 a barrel, with fresh strikes near Iran's Kharg Island oil export hub.
The Nikkei 225 lost 182.1 points or 0.3% to open at 65,087.22.
Market sentiment in Asia remained cautious as investors await Friday's U.S. inflation data, which will shape expectations for the Federal Reserve's September meeting.
Elsewhere, the White House announced new trade measures Tuesday, signing orders to block Canadian motorcycles, dairy, and alcoholic drinks.