United Nations Secretary-General Antonio Guterres said on Saturday that a nuclear war cannot be won and must not be fought.

“The use of nuclear weapons would affect all states, meaning that all states have a responsibility to ensure that such deadly armaments are never used again and are eliminated completely from national arsenals,” the secretary-general said in his message on the International Day for the Total Elimination of Nuclear Weapons, reports AFP.

Calling on states that possess nuclear weapons “to return to real, good-faith dialogue to restore trust and confidence, reduce nuclear risk and take tangible steps in nuclear disarmament,” the UN chief said that “they should reaffirm the shared understanding that a nuclear war cannot be won and must not be fought. They should take steps to implement the commitments they have undertaken.”

The UN General Assembly declared the international day in December 2013, in its resolution 68/32 as a follow-up to the high-level meeting of the General Assembly on nuclear disarmament held on Sept. 26, 2013, in New York. This day provides an occasion for the world community to reaffirm its commitment to global nuclear disarmament as a priority.

It provides an opportunity to educate the public – and their leaders – about the real benefits of eliminating such weapons, and the social and economic costs of perpetuating them.