UN Secretary General Ban Ki-moon on Tuesday called for the UN Conference on Disarmament to end years of stalemate over Pakistan's reluctance to discuss a ban on the production of fissile material for nuclear weapons.

Ban stressed the importance of the conference, which due to a consensus requirement has been deadlocked for four years because Pakistan has refused to allow talks to get started towards a treaty banning further production of fissile material.

"It is essential to end this continued stalemate to avoid jeopardising the credibility of the conference and the machinery of disarmament," Ban said in a statement that was read out by the top UN official in Geneva, Kassym-Jomart Tokayev, at the first of the conference's public sessions this year.

"The world today remains over-armed. Peace is under-funded. We cannot afford to lose yet another year," he added, urging the conference to "resume your primary task of negotiating multilateral disarmament treaties."

Citing his predecessor, Swedish diplomat Dag Hammerskjold, who served as UN chief from 1953 to 1961, Ban stressed that in the field of disarmament "a standstill does not exist; if you do not go forward, you go backward."

The UN conference, he insisted, "has the potential to again be central to disarmament negotiations."

"Let us ensure it lives up to its responsibility."

Ban's frustration was echoed in remarks from many countries represented at the Geneva meeting.

"There is a lot of dispair," a diplomatic source who asked not to be named told AFP.

Taking advantage of a new climate established by US President Barack Obama, the conference emerged in May 2009 from 12 years of obscurity, adopting for the first time since 1996 a programme of negotiations on fissile materials and weapons.

But the reluctance of Pakistan to accept a possible treaty banning the production of fissile material for nuclear weapons has since then prevented the conference from moving forward.

The council ends its first session of this year on March 28.