Leonardo DiCaprio, UN Messenger of Peace with a special focus on climate change, opened the UN Climate Summit this morning.

"As an actor, I pretend for a living," Mr. DiCaprio said to gathered leaders and press in New York City. "I believe that mankind has looked at climate change in that same way, as if it were fiction, as if pretending it weren't real would make it go away."

The actor, who in June pledged $7 million to to marine life protection in U.S. waters of the Pacific Ocean, also called out the private sector for its role in causing, and solving, climate change issues. "They do not deserve our tax dollars—they deserve our scrutiny. The economy itself will die if our ecosystems collapse."

He called on leaders to step up to address what he says is an "achievable problem" and to ensure that access to clean air and clean water are viewed as inalienable human rights. "You can make history, or you can be vilified by it," he stated, asking leaders to face climate change head on "with courage and honesty."

Managing editor Chrisella Herzog is reporting live from the UN General Assembly in New York City. For more updates, follow the Diplomatic Courier on Twitter: @DiploCourier.

The views presented in this article are the author’s own and do not necessarily represent the views of any other organization.