Apple Inc. (Nasdaq: AAPL) said it’s rejoining an environmental rating system after its exit from the group threatened to halt sales to governments and universities that use the registry when making purchasing decisions.

Apple’s decision to drop out of the environmental system called EPEAT was a “mistake” and its eligible products are now back on the registry, Bob Mansfield, Apple’s senior vice president for hardware engineering, said in a statement posted on the company’s website.

“It’s important to know that our commitment to protecting the environment has never changed, and today it is as strong as ever,” Mansfield said in the statement.

Apple told EPEAT that it was withdrawing its products from the list on June 29, and said it did not plan to submit its products for ratings in the future.

The list is considered an industry standard and it helps customers buy electronics that are environmentally friendly. Some municipalities also use it to guide their decisions in buying electronics.

San Francisco officials said earlier this week that the city planned to suspend purchases of Apple computers after it withdrew from the rating system, which is used to determine the environmental impact of electronics. Many colleges that use EPEAT to guide purchasing decisions, including the University of California, said they were considering following suit.

“Our relationship with EPEAT has become stronger as a result of this experience,” Mansfield said, adding that the company would be working with the group to help the current rating system “evolve.”

Robert Frisbee, EPEAT’s chief executive officer, said the group “looked forward to Apple’s strong creative thoughts on ongoing standards development.”

‘Natural Alignment’

“Our relationship with Apple is based on our natural alignment,” Frisbee said in a statement on EPEAT’s website. “As Apple drives innovation in product design, EPEAT drives innovation in standards design.”

Greenpeace International, an environmental group that has previously criticized Apple’s energy consumption, commended the company’s return to the EPEAT registry.

“We applaud Apple for ’thinking green, not greedy’ and listening to its customers’ calls not to pit design needs against the environment,” Greenpeace said in a statement. “We await more details that ensure that future versions of Apple’s computers will be built with easily removable, recyclable and upgradable parts, unlike the current MacBook Pro.”

The San Francisco Department of the Environment said it was “pleased to learn that Apple is rejoining EPEAT.”

“Independent standards, eco-labels and registries like EPEAT are critical tools for verifying the environmental integrity of products for consumers,” Melanie Nutter, director of the department, said in a statement.

(Bloomberg and The AP contributed to this report.)