Seeking to turn the tables in the controversy over high-profile defections from the U.S. Chamber of Commerce, President Tom Donohue told reporters today that members are facing orchestrated pressure from environmental groups to quit the chamber and that his organization fully supports taking action to reduce greenhouse gas emissions.

In an hour-long sit-down with about a dozen reporters this morning at the chamber's headquarters, Donohue repeatedly said that he's "not particularly worried" about the recent defections, which have included Apple and the major utilities Exelon, PNM Resources and Pacific Gas & Electric.

"I'm worried about making sure people understand what we believe, what we're trying to achieve and who we're trying to do this for," he said. He didn't, however, say which environmental groups were pressuring the chamber's members.