On May 9, 2009, Salazar announced the upholding of a Bush-era policy that prevents the regulation of greenhouse gas emissions via the Endangered Species Act (ESA), a policy he pledged to reevaluate when he took office in January. The policy states that, despite the apparent negative impact global warming has on polar bears, an endangered species, greenhouse gasses cannot be regulated with the ESA. Salazar stated in a conference call announcing the decision that "The single greatest threat to the polar bear is the melting of Arctic Sea ice due to climate change," but the Endangered Species Act "is not the appropriate tool for us to deal with what is a global issue." The decision was met with criticism from environmental groups and praise from energy groups including the American Petroleum Institute, some Democrats and many Republicans. Salazar contended in the same conference call that the ESA was never intended to be used for the regulation of climate change, while sidestepping questions of how this situation is different from that of the Clean Air Act, which is currently being used by the Environmental Protection Agency to regulate emissions.