The UN chief emphasized Tuesday the imperative of a binding ban on nuclear tests for a nuclear-free world and urged an immediate halt to testing. 

Antonio Guterres appealed to all nations to ratify the Comprehensive Nuclear Test Ban Treaty, without conditions, at an event to mark International Day Against Nuclear Tests at the General Assembly.

"Since 1945, more than 2,000 nuclear tests have inflicted terrifying suffering on people, poisoned the air we breathe, and ravaged landscapes around the world," said Guterres.

"This year, we face an alarming rise in global mistrust and division. At a time in which nearly 13,000 nuclear weapons are stockpiled around the world -- and countries are working to improve their accuracy, reach and destructive power -- this is a recipe for annihilation," he said.

"A legally binding prohibition on nuclear tests is a fundamental step in our quest for a world free of nuclear weapons," said Guterres. "Let’s end nuclear testing forever."

The day has been observed annually on Aug. 29 since 2010.

President of the UN General Assembly Csaba Korosi said every effort should be made to end nuclear tests.

"It is our duty to ensure that the ban on nuclear testing is legally binding for all states. We need the right policies and safeguards to protect us against mistakes and poor decision-making," he added.