In a message on the International Day Against Nuclear Tests, the UN chief said, "Our collective security demands that every effort should be made to bring this essential treaty into force."
He said the history of nuclear testing is one of suffering, with the victims of more than 2,000 nuclear tests often from the most vulnerable communities around the world.
The devastating consequences – which were not confined by international borders -- encompassed impacts on the environment, health, food security and economic development, said Guterres.
Since the end of the Cold War, a robust norm has developed against nuclear testing, violated by only one State this century, he said.
The strength of that norm has been validated by the international community’s overwhelming condemnation of each violation, Guterres said.
Nevertheless, Guterres said the restraint displayed through voluntary moratoria cannot replace a global, legally-binding ban on nuclear-testing.
"The Comprehensive Nuclear-Test-Ban Treaty has an essential role within the nuclear disarmament and non-proliferation regime," the UN chief said.
He said it fosters international peace and security by constraining the development of nuclear weapons.