In his first major speech on climate change since taking office five months ago, UN Secretary-General António Guterres urged a bold and united front against the global challenge of climate change. Guterres emphasized that if any one country withdraws from or fails to implement the Paris Agreement on climate change, all other nations have the responsibility to redouble their efforts to fulfill their climate commitments.

“If any government doubts the global will and need for this accord, that is reason for all others to unite even stronger and stay the course,” he told the audience of students, scientists, business people, and citizens at New York University’s Stern School of Business.

“The message is simple: the sustainability train has left the station. Get on board or get left behind.”