NASHVILLE (AP) — Tennessee Gov. Bill Lee says the state has a duty to protect the environment, but held off from agreeing humans are the reason behind climate change.

The Republican fielded questions about climate change while talking to reporters last week after speaking at the Nashville Chamber of Commerce's annual breakfast.

Lee also said climate change studies have shown "different outcomes" when it comes to reason why, but added he wanted to be a "responsible steward" of the environment in Tennessee.

The vast majority of peer-reviewed studies, science organizations and climate scientists agree the world is warming, mainly due to rising levels of carbon dioxide and other greenhouse gases. Most of the increase in temperature comes from man-made sources, including the burning of coal, oil and natural gas, deforestation and livestock raising.