Apple, which made news in environmental circles recently with its new approach to environmental accounting, took another high-profile action on climate change Monday when it resigned its membership in the U.S. Chamber of Commerce over the group's environmental policies.

Apple became just the latest defection from the business lobbying group. And given that Apple's every move generates buckets of publicity, the action may serve to thrust the climate change issue into greater focus for the buying public.

Last month three big power utilities -- Exelon Corp, PG&E Corp and PNM Resources Inc -- said they were leaving the Chamber over its stance on global warming legislation. Nike last week resigned from the board of the Chamber, which has pushed for public hearings to challenge the scientific evidence of manmade climate change.

Apple made its resignation in a letter to Chamber CEO Thomas Donohue:

"As a company, we are working hard to reduce our own greenhouse gas emissions ... We have undertaken this unilaterally and without government mandate, because we believe it is the right thing to do. For those companies who cannot or will not do the same, Apple supports regulating greenhouse gas emissions, and it is frustrating to find the Chamber at odds with us in this effort."

"We would prefer that the Chamber take a more progressive stance on this critical issue and play a constructive role in addressing the climate crisis. However, because the Chamber's position differs so sharply with Apple's, we have decided to resign our membership effective immediately."