Former President Barack Obama reflected on the life of former United Nations Secretary-General Kofi Annan on Saturday following news of his death, per HuffPost.

Obama took to Facebook and paid respects to Annan for his diplomatic and humanitarian work.

“Kofi Annan was a diplomat and humanitarian who embodied the mission of the United Nations like few others,” Obama said in a Facebook post. “His integrity, persistence, optimism, and sense of our common humanity always informed his outreach to the community of nations. Long after he had broken barriers, Kofi never stopped his pursuit of a better world, and made time to motivate and inspire the next generation of leaders. Michelle and I offer our condolences to his family and many loved ones.”

While Annan, who died surrounded by his wife and three kids on Saturday, left his position as UN chief before Obama became President in 2009, he had publicly congratulated him for his win saying, “demonstrates America’s extraordinary capacity to renew itself and adapt to a changing world,” per HuffPost.

Annan served as the UN’s seventh Secretary-General from 1997 to 2006. He was the first Black African to head the global organization.

He won the Nobel Peace Prize in for his “work for a better organized and more peaceful world.”