The Nikkei 225 and Topix indexes rallied nearly 2% on Wednesday, with the latter reaching one-year highs after US President Donald Trump announced a trade agreement with Japan that includes a 15% tariff on Japanese exports to the US. Trump also revealed that Japan will invest $550 billion into the US and open its markets to key American goods. The news sparked broad-based gains, led by Japanese automakers. Toyota Motor jumped 9.8%, Honda Motor rose 8.8%, and Nissan Motor climbed 9%. Financials, industrials, and consumer stocks also posted strong advances, reflecting optimism over improved trade relations. In contrast, technology shares lagged the broader market, tracking losses in US tech stocks overnight. Separately, reports indicated that Prime Minister Shigeru Ishiba is weighing whether to step down, pending the outcome of tariff negotiations.