One of the reasons behind the civil war in Syria may be climate change, Britain’s Prince Charles suggested in an interview with Sky News, to be telecast later Monday. The Prince of Wales also expressed concerns that the world was heading toward “catastrophes and chaos” if environmental issues were not addressed.

Charles’ interview came ahead of his speech at the opening ceremony for COP21, the United Nations conference on climate change on Nov. 30 in Paris. In the interview, shot three weeks ago and before the Paris attacks, Charles said Syrians were forced to leave their land because of several years of drought.

“We’re seeing a classic case of not dealing with the problem, because, I mean, it sounds awful to say, but some of us were saying 20 something years ago that if we didn’t tackle these issues you would see ever greater conflict over scarce resources and ever greater difficulties over drought, and the accumulating effect of climate change, which means that people have to move.

“And, in fact, there’s very good evidence indeed that one of the major reasons for this horror in Syria, was a drought that lasted for about five or six years, which meant that huge numbers of people in the end had to leave the land,” the 67-year-old heir to the British throne told Sky News.

When asked whether environmental issues were directly associated with conflict and terrorism, Charles said that the Pentagon began paying attention to this link in the “last few years.” He added that climate change had a huge impact on the current situation in the world. Charles also explained to Sky News that the climate change issue has been addressed with a short-term method that overlooked the “underlying root cause” of what mankind was doing to the environment.

The prince has been vocal about issues concerning the environment. In 2007 he established the Prince’s Rainforest Group to save the threatened forests of the world. He addressed a U.N. international climate summit in Copenhagen in 2009 and in 2010 delivered a speech to the Oslo Climate and Forest Conference.

Meanwhile, the United Nations said Monday that weather-related disasters have claimed 600,000 lives globally in the past two decades. The U.N. report claimed that an additional 14 billion people were “injured, left homeless or in need of emergency assistance.” The organization also called for countries to settle on a landmark deal on climate change, Agence France-Presse reported.