U.S. tech stocks tumbled in early Friday trading, extending one of the worst days for the Nasdaq in five years, as China hit back at President Donald Trump's sweeping global tariffs with new levies that look set to trigger a damaging trade war between the world's two biggest economies.

The company counts on the sale of devices for three-quarters of its nearly $400 billion in annual revenue, and it makes almost all of its iPhones, iPads and Macs overseas.

Then there is the risk to sales in China, he adds. Apple’s revenues in the country fell by 8% last year, mostly because of weakness in demand for iPhones and iPads. Chinese consumers may accelerate that slide by treating Apple as a scapegoat for Mr Trump’s antics. The appeal of home-grown alternatives, such as Huawei, Oppo and Xiaomi, is growing.

A Japanese chipmaker you've probably never heard of wants to power Apple's future artificial intelligence server farms.

Shares in some of the biggest U.S. technology and consumer firms fell late Wednesday following President Trump's announcement of significant tariffs, including 34% on China and 46% on Vietnam, nations that export large amounts of goods to America.

President Trump’s sweeping new slate of tariffs is poised to strike a blow at the tech industry, as massive import taxes on China and Taiwan disrupt trade flows that are central to tech firms’