Apple said said the new policy would be in effect until it can confirm that companies in its supply chain for the metal, used in iPhone and iPad batteries, have “appropriate protections” safeguarding workers and banning child labor, a company spokesperson told the Washington Post on Friday. The spokesperson added that all small mines must meet its workplace standards to qualify as suppliers.

The announcement follows a recent report by U.K. broadcaster Sky News, which investigated the state of cobalt mine working conditions in the Congo. The investigation found several children, including an eight-year-old named Dorsen, who worked 12-hour days carrying heavy sacks in sometimes heavy rain while supervisors threatened them with beatings. An 11-year-old worker, Richard, told Sky News that his body “ached” each day following his shift.

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All of the workers—children or otherwise—suffer harsh working conditions with no protective equipment, according to the report. Hand-dug tunnels are at constant risk of collapse, leading to worker deaths, Sky News reported, based on interviews with workers. Those workers were extracting cobalt that eventually made its way into major technology company supply chains, including Apple’s (AAPL), to be used in lithium-ion batteries. Without it, the batteries, which power everything from iPhones to computers, wouldn’t work. Congo supplies 60% of the world’s cobalt.

The technology industry’s cobalt problem was initially highlighted last year when the Washington Post published an investigation into Congo’s artisanal cobalt supply chain. Like the Sky News report, the Post found dangerous working conditions and child labor.

The Post‘s report centered on a Chinese company, Zhejiang Huayou Cobalt Company, Congo’s biggest cobalt buyer and an Apple supplier. The company buys minerals from some artisanal mines that employ children and have harsh working conditions, according to the report.

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Apple has been among the more transparent technology companies in detailing its supply chain and standards to which it tries to hold its suppliers. Each year, the company releases a report detailing progress in its supply chain and the actions it takes to ensure workers are treated fairly. In some cases, Apple discovers instances in which its working conditions regulations are violated by suppliers.

“There’s a right way to make products,” Apple said in the introduction of its report in 2016. “It starts with the rights of the people who make them.”

After the Post‘s investigation into cobalt last year, Apple said that it would address the concerns in its supply chain but wouldn’t stop sourcing cobalt from artisanal mines. In light of the Sky News report, Apple has taken more action. In addition to halting artisanal mine orders, Apple told the Post that it will begin to treat cobalt in the same way as conflict minerals like gold and tungsten, and increase scrutiny on the mineral’s mining.

Neither Apple nor Huayou responded to Fortune‘s request for comment on the report.