THE UNITED NATIONS - “I reiterate my call for all States that have not yet done so, to sign and ratify the [Comprehensive Nuclear-Test-Ban Treaty], especially those whose ratification is needed for the Treaty’s entry into force,” Mr. Guterres urged in his message for the International Day Against Nuclear Tests, observed annually on 29 August.

The Treaty, known worldwide by the acronym CTBT, is a central pillar of international efforts to advancing nuclear disarmament.

However, despite being widely supported – with 184 signatories and 168 ratifying States – it has not yet entered into force, more than two decades after its adoption.

“Honoring those victims requires bringing nuclear testing to a permanent end,” said the Secretary-General, stressing that “yet, an effective and legally-binding prohibition remains one of the longest unfulfilled goals of nuclear disarmament.”

The UN chief stressed that the CTBT is vital to ensuring there are no more victims; it is also essential to advancing nuclear disarmament.

The International Day against Nuclear Tests marks the closing, in 1991, of the nuclear test site in Semipalatinsk, Kazakhstan, the largest in the former Soviet Union. More than 450 tests took place there, with impacts still being felt decades later.

The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) is a Vienna-based international organization that will be established upon the entry into force of the CTBT. It will be tasked with verifying the ban and will operate therefore a worldwide monitoring system and may conduct onsite inspections.

The Preparatory Commission for the CTBTO, a UN partner forum, was set up in 1997 and consists of a plenary body composed of all States signatories to the Treaty and a Provisional Technical Secretariat.