Pope Francis is calling for swift action to protect the environment and fight climate change in a highly anticipated letter released Thursday by the Vatican. Washington bureau reporter Geoff Bennett filed the following report.

Pope Francis is lending his stature and influence to the goals of the environmental movement. The pontiff cites both science and scripture to frame the battle against climate change as a moral obligation.

It's all outlined in a public letter, known as an encyclical.

"As far as an authoritative papal teaching, this is as high as it gets," said the Reverend Monsignor Kevin Irwin, a priest at The Catholic University of America.

Pope Francis and his advisers have been working on the document for more than a year. It calls on everyone, not just Catholics, to show respect for their creator by caring for creation. 

"Our theology of creation is not separate from saving our soul; it's part of the same thing," Irwin noted.

In the encyclical, Francis accepts the science of climate change and says it's mostly man-made. He calls for sustainable development and argues that the continued use of fossil fuels poses "grave consequences."

“He sees environmental threats as a threat to human life, a threat to human dignity," said John Carr, director of the Initiative on Catholic Social Thought and Public Life at Georgetown University.

It's a threat, which the Pope says, is shouldered mostly by developing countries. The Pope writes that the world’s poor bear the brunt of the "enormous consumption" of the rich. 

Devotion to the poor is a cornerstone of Francis' papacy, evident in the name he chose when he was elected. 

"He said, 'Francis was the a saint of the poor, a saint of creation and a saint of peace.' In some ways, this encyclical was in his head then because it puts together the poor, creation and peace," Carr said.

The release comes ahead of the Pope’s planned trip to the United States later this year, where he is due to address the United Nations and a joint meeting of Congress. The document is already forcing some high-profile Republicans to break with the pontiff on the issue of climate change.

"Religion ought to be about making us better as people and less about the things that end up getting into the political realm," said Republican presidential candidate Jeb Bush.

"Frankly, we have plenty of politics in these discussions. We need a little faith and morality," Carr added.

The Vatican hopes the document will influence the debate at a major U.N. summit on climate change, which is being held in Paris this December. 

More than 190 countries will try to reach an agreement to limit greenhouse gas emissions.