UN General Assembly (UNGA) President Miroslav Lajcak said that besides human suffering and planet contamination, nuclear tests also pose political threat as they do not build trust.
"The last century has seen massive advancement in nuclear science and technology. And this has led to many benefits. But, also, indescribable pain," Lajcak said in his opening remarks at a high-level meeting to commemorate the International Day against Nuclear Tests that falls on Aug. 29.
Since nuclear weapons testing began in 1945, nearly 2,000 have taken place. "Some of which, unfortunately, happened not that long ago," he said.
"These tests do not build trust. Instead, they escalate tensions. They create openings for political miscalculations, and they bring us closer to the brink," he warned.
The UNGA chief said the Comprehensive Nuclear Test Ban Treaty, which was adopted in 1996 and has since been open for signature, "offers us our best shot at making nuclear tests a thing of the past," urging member states' support for entering the treaty into force.
Turning to the developments on the Korean Peninsula, Lajcak commended the past year's progress towards denuclearization.
"This time last year, things looked bleak... Now, we can see the opportunity," he said, noting "positive steps have been taken by the Democratic People's Republic of Korea -- including the suspension of nuclear tests and launches of inter-continental ballistic missiles, as well as the closure of a nuclear test site."
At the same time, he urged more tangible action on the Korean Peninsula, stressing "verification is crucial for progress."
UN Secretary-General Antonio Guterres spoke after Lajcak at the high-level meeting.
He recalled his visit in July to Japan's Nagasaki where he met with survivors of the atomic bomb attack.
"Through the testimony of the survivors, the Hibakusha, we are reminded of the need to ensure that nuclear weapons are never used again," he stressed.
The UN chief also noted the victims of the disastrous era of widespread nuclear testing, saying "the catastrophic impact of nuclear testing has had profound effects on the environment, human health, food security and economic development."
On Dec. 2, 2009, the UN General Assembly unanimously adopted a resolution to declare Aug. 29 the International Day against Nuclear Tests.
The resolution was initiated with a view to commemorating the closure of the Semipalatinsk nuclear test site in Kazakhstan on Aug. 29, 1991.
The Day is meant to galvanize the UN, member states, intergovernmental and non-governmental organizations, academic institutions, youth networks and the media to inform, educate and advocate the necessity of banning nuclear weapon tests as a valuable step towards achieving a safer world.