A customer departs an Apple store after people queued up for the launch of the new iPhone 14 in Tokyo on September 16, 2022.(Richard A. Brooks / AFP)

TOKYO — Apple Inc said on Tuesday it had invested more than $100 billion in its Japanese supply network over the last five years, as its Chief Executive Officer Tim Cook visited the epicentre of the country's semiconductor industry.

Cook said in a Monday tweet he visited Kumamoto prefecture in southwestern Japan, home to factories of many semiconductor and leading technology firms, including one under construction by Taiwan Semiconductor Manufacturing Co.

Apple said it had boosted its spending on suppliers in Japan by more than 30% since 2019

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In a statement, Apple said it had boosted its spending on suppliers in Japan by more than 30 percent since 2019, with a network spanning nearly 1,000 companies, from multi-nationals to family-run businesses.

It called Sony Group Corp one of its biggest suppliers in Japan for providing camera sensors for iPhone products, while also mentioning medium- and small enterprises including textile firm Inoue Ribbon Industry Co and mold manufacturer Shincron Co as partners.

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Apple said 29 Japanese suppliers have committed to converting to renewable energy for Apple-related businesses by 2030, including Sony, Murata Manufacturing Co, Keiwa Inc, Fujikura and Sumitomo Electric Industries.