[3] He also set up the 1987 Africa Fund as Prime Minister Rajiv Gandhi's Special Envoy and was India's representative on UNESCO's Executive Board.
In a diplomatic career spanning more than three decades, he held several senior diplomatic positions, including: Ambassador and Permanent Representative to the UN, Geneva (1967-70); Ambassador to Yugoslavia and Greece (1976-79); Additional Secretary, Ministry of External Affairs (1979-81); Permanent Representative to the UN, New York (1981-86) and President of the UN Security Council in February 1985; and Chairman of the Coordinating Bureau of the Non-Aligned Countries (1983-86).
After retiring from the Indian Foreign Service in 1986, he was appointed as Special Envoy by Prime Minister Rajiv Gandhi to set up the Africa Fund to assist Southern African front-line states threatened by the apartheid South African government.
Later, Mr Krishnan helped to found and became the first Dean of the School of International Studies at Pondicherry University .
When the war between Iran and Iraq broke out, the two countries failed to reach to peace deal.