– Pope Francis is days away from releasing what the Guardian predicts will be "his most radical statement" yet, and he says it isn't just for Catholics. Francis will be accompanied by an atheist climate scientist and a Greek Orthodox theologian, as well as a Vatican cardinal, when he releases his long-anticipated letter on the environment on Thursday, the AP reports. The encyclical, a rare papal "teaching letter," is expected to focus on climate change, humanity's role in causing it, and its devastating and disproportionate effects on the world's poor, reports the New York Times, which notes that Francis has long been outspoken on environmental issues and told reporters earlier this year that "man has slapped nature in the face." In a recent speech seen as a preview to the encyclical, Francis made it clear that he believes climate change and the suffering of the poor is the result of capitalism and overconsumption, the Guardian reports. "Much of the world remains in poverty, despite abundant resources, while a privileged global elite controls the bulk of the world's wealth and consumes the bulk of its resources," he said. Climate scientists say since the issue has become an ideological and partisan one as much as it is a scientific one, the papal letter could do more than international negotiations this year to reduce emissions, USA Today reports. (A US conservative group claims Francis has been "misled" on the issue, and staunch Catholic Rick Santorum says he finds the church leader hard to listen to.)