The Nikkei 225 Index fell 0.81% to 63,493 on Monday, its lowest level in six weeks, as losses in US stock futures and concerns about safety risks in advanced artificial intelligence development weighed on sentiment. Anthropic CEO Dario Amodei called on AI companies Saturday to slow development of their most advanced models. Oil prices also surged after Saudi Arabia shut the East-West pipeline, an alternative route around the Strait of Hormuz. Higher energy costs strengthened expectations that the US Federal Reserve and the Bank of Japan will raise interest rates this week. Technology and AI-linked shares led the decline, including Kioxia Holdings, Advantest and Taiyo Yuden. SoftBank Group plunged 10.7% after OpenAI CEO Sam Altman said the ChatGPT maker would not pursue an initial public offering this year.