Iran has accused the world's five largest nuclear powers of failing to take concrete action to eliminate their stockpiles and called for negotiations on a convention to achieve nuclear disarmament by a target date.

Iran's deputy UN ambassador Gholam Hossein Dehghani on Wednesday told the UN Disarmament Commission that "a comprehensive, binding, irreversible, verifiable" treaty was the most effective and practical way to eliminate nuclear weapons.

Dehghani accused the nuclear powers - the US, Russia, China, Britain and France - of promising nuclear disarmament but making no significant progress.

Dehghani's speech came days after the announcement of a framework agreement between Iran and the five nuclear powers and Germany aimed at keeping Tehran from being able to develop a nuclear weapon. The historic pact has to be finalised by June 30.

The commission, which includes all 193 member states, is supposed to make recommendations in the field of disarmament but has failed to make substantive proposals in the past decade.

Its three-week meeting is taking place ahead of the five-year review of the Nuclear Non-Proliferation Treaty (NPT), the world's single most important pact on nuclear arms, which begins on April 27.

The NPT is credited with preventing the spread of nuclear weapons to dozens of nations since entering into force in 1970. It has done that via a global bargain: Nations without nuclear weapons committed not to

acquire them; those with them committed to move towards their elimination; and all endorsed everyone's right to develop peaceful nuclear energy.

Dehghani said that as a non-nuclear weapon state and NPT member, Iran believed it was time to end the incremental approach towards disarmament and to start negotiations with all nuclear and non-nuclear weapon states on a convention that would set a deadline for ridding the world of nuclear weapons.

He noted that a proposal in 2013 by the Non-Aligned Movement, which represents over 100 developing countries, to start negotiations on a comprehensive nuclear weapons convention in the Conference on Disarmament gained wide support.

Iran's call echoed

Russia said President Vladimir Putin has confirmed that Moscow is ready for a serious and substantive dialogue on nuclear disarmament.

But Olga Kuznetsova, a counsellor in Russia's Foreign Ministry, warned in a speech on Tuesday that the US deployment of a global missile defence system could lead to the resumption of a nuclear arms race.

The only way to change the situation, she said, was for states that pursue anti-missile capabilities to follow the "universal principle" of not trying to strengthen their security at the expense of the security of other states.

Kuznetsova also warned that development of high-precision non-nuclear weapons threatened "strategic parity" between the two nuclear powers and could lead to "global destabilisation of [the] international situation in general".

Chinese counsellor Sun Lei urged countries to "abandon Cold War mentality" and said those with the largest nuclear arsenals should be the first to make "drastic and substantive" cuts in their nuclear weapons.

Ukraine's representative called for the urgent development of a binding agreement that would give assurances to countries without nuclear weapons that they will not be threatened by nuclear weapons. Pakistan's Ambassador Maleeha Lodhi echoed that call.

The US said the negotiation of a treaty that would cap available fissile material was "the next logical step on the multilateral nuclear disarmament agenda". Its representative John Bravaco said the US had not produced fissile material for nuclear weapons since 1989.

North Korea's deputy UN ambassador, An Myong Hun, declared that "our nuclear forces are the life and soul of our nation" and would not be given up as long as nuclear threats remained.

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