Secretary-General Ban Ki-moon on Monday urged negotiations to start immediately on a new treaty banning production of nuclear bomb material, according to AP. The secretary-general told reporters before heading to Washington to attend a nuclear security summit hosted by President Barack Obama that he has repeatedly called for the 65-nation Conference on Disarmament to start treaty talks because «nuclear terrorism is one of the greatest threats we face today.» «That is why, in Washington, I will call on all world leaders to come together, perhaps at the United Nations in September, to further advance this essential cause for humankind,» Ban said. In January, Pakistan delayed the start of talks on a Fissile Material Cutoff Treaty that would ban production of highly enriched uranium and plutonium, insisting that any deal must also require its archrival India to reduce its existing stockpile of nuclear material. Obama last year called for a verifiable ban on new nuclear material under a Fissile Material Cutoff Treaty. The administration of former U.S. President George W. Bush had objected to such a deal. The Conference on Disarmament, based in Geneva, can only move forward by consensus. It has failed to produce any deal of substance since the 1996 Comprehensive Nuclear Test Ban Treaty. The secretary-general said «it was encouraging that the Conference on Disarmament had agreed to the program of work» for 2010, which it has not done for several years. «But they have not made any substantial progress in terms of their work, so I'm urging them to make progress in their substantive discussions, and particularly in preventing the production of fissile material,» Ban said. A five-year review of the Nuclear Nonproliferation Treaty is scheduled next month, and Ban said «we can see new momentum toward our ultimate ambition, a world free of nuclear weapons.» The NPT is considered the cornerstone of global nuclear disarmament efforts. Nuclear powers India and Pakistan and Israel, which is widely believed to possess nuclear weapons, are not parties to the NPT. North Korea, which has conducted two nuclear tests, pulled out of the NPT. The approvals of nine nations are still required for the nuclear test-ban treaty to take effect _ the United States, North Korea, Pakistan, India, Iran, Israel, China, Egypt and Indonesia.