Gorbachev did more than others for peaceful end of Cold War - UN Secretary-General

"I was deeply saddened to learn of the passing of Mikhail Gorbachev, a one-of-a kind statesman who changed the course of history. He did more than any other individual to bring about the peaceful end of the Cold War," Guterres said.

"On behalf of the United Nations, I extend my heartfelt condolences to Mikhail Gorbachev's family and to the people and government of the Russian Federation," he said.

Gorbachev died after a long illness on Tuesday evening.

According to Guterres, Gorbachev, receiving the 1990 Nobel Peace Prize, "observed that 'peace is not unity in similarity but unity in diversity.'"

The UN chief said Gorbachev put that vital insight into practice by pursuing the path of negotiation, reform, transparency and disarmament.

"In his later years, Mikhail Gorbachev embraced a new challenge just as vital for the wellbeing of humankind: creating a sustainable future by cultivating harmonious relationships between humans and the environment. It was in this spirit that he founded Green Cross International. The world has lost a towering global leader, committed multilateralist, and tireless advocate for peace," Guterres said.