The Nikkei 225 Index rose 0.6% to close at 58,825, while the broader Topix Index gained 0.43% to 3,777 on Monday, recovering some losses from the previous session as renewed enthusiasm for artificial intelligence stocks outweighed concerns over escalating US-Iran tensions. The US seized an Iranian-flagged cargo vessel in the Gulf of Oman, while Tehran reversed plans to reopen the Strait of Hormuz and said it would not take part in a second round of negotiations. Ongoing disruptions in the strategic waterway have triggered a severe energy supply shock, heightening inflation risks and threatening global growth, with oil-importing economies such as Japan particularly vulnerable. Still, AI-driven optimism and corporate earnings supported domestic equities, with notable gains from SoftBank Group (5.5%), Lasertec (5.4%), and Unitika (21.4%).