Christiana Figueres will step down as Executive Secretary of the United Nations Framework Convention on Climate Change when her six-year term ends July 6.

“It is with deep gratitude to all of you that I write to formally announce that I will serve out my term as Executive Secretary of the United Nations Framework Convention on Climate Change, which finishes on July 6, 2016, and not accept an extension of my appointment,” the Costa Rican diplomat wrote February 12.

“We now move into a phase of urgent implementation,” stressed Figueres, who helped lead the push for the Paris Agreement last year. “The journey that lies ahead will require continued determination, ingenuity and, above all, our collective sense of humanity and purpose. I know that together you will again rise to the task.”