Japan's Nikkei closes at record as AI rally helps overcome early losses

TOKYO, Sept 24 (Reuters) - Japan's Nikkei share average closed at a record high on Wednesday, fighting back from early losses on optimism buoyed by investments in artificial intelligence.

The Nikkei 225 Index .N225 rose 0.3% to close at an unprecedented 45,630.31, recovering from earlier session losses as wide as 0.6%. The broader Topix .TOPX gauge gained 0.2%.

Investor enthusiasm over AI has been a major driver in Wall Street and Japanese shares vaulting to ever higher records.

OpenAI, Oracle ORCL.N, and Japan's SoftBank Group 9984.T on Tuesday unveiled plans for five new AI data centres in the United States to build out their ambitious Stargate project.

Wednesday's early declines were a corrective move after the index's recent surge, while tech shares provided support, said Nomura strategist Maki Sawada.

"We continue to see AI-related and data centre-related stocks holding up well," she added.

There were 100 advancers on the benchmark against 121 decliners. Its 14-day relative strength index (RSI) began the session above 70, indicating an overheated market.

The Nikkei's largest gainers were industrial manufacturer IHI 7013.T, which rose 9.7%, followed by SoftBank Group, which jumped 6%.

The sharpest falls were in shares of utility Tokyo Electric Power 9501.T, which was down 4.89%, followed by video game maker Nexon 3659.T, which sank 3.8%.