China has locked down the zone around the world’s largest iPhone factory with zero notice, causing a huge headache for Apple, who won’t able to move product in and out of the factory.

Foxconn’s Zhengzhou plant produces hundreds of thousands of units a day during peak production. The company has been operating on a closed loop for weeks, after a Covid outbreak. The factory has been hit with food shortages, and worker outcries, with a number of employees filmed earlier this week scaling walls to get out.

Just last week, the company insisted things were under control.

“At present, the epidemic prevention work in Zhengzhou is progressing steadily, and the impact on the group is controllable,” Foxconn said.

“The operating outlook for this quarter remains unchanged.”

This latest lockdown makes matters worse, as no additional workers are allowed in to replace those who have left.

Local authorities will “sterilise Foxconn’s campus and the surrounding areas in the next three days and send N95 face masks to workers”, Bloomberg reports.

Although Foxconn has boosted iPhone production at another facility in Shenzhen, its 200,000 strong Zhengzhou workforce is vital to Apple hitting its production target.

Foxconn is Apple’s biggest iPhone vendor, accounting for up to 70 per cent of global iPhone shipments annually.

“The Zhengzhou plant plays a monumental role in increasing capacity ahead of the holiday season,” said Nicole Peng, an analyst with Canalys.

“Some of the orders generated in holiday promotional campaigns may not be able to be immediately delivered. Product delivery in certain channels could also be delayed.”

Foxconn will continue to operate the plant on a ‘closed loop’ system, basically a bubble in which the workers travel between dorms and the factory.

The major problem this recent lockdown poses is the ability to ship iPhones and necessary parts in and out of the factory.

Foxconn have not addressed this, but Zhengzhou’s lockdown notice bans any products entering or exiting aside from medical supplies and other essential items.

Chinese media reported earlier this week that Apple had already lowered its production targets by as much as 30 per cent before this latest lockdown.