Unless the world abandons the supposition that nuclear weapons guarantee security, it risks a return to the "mutual assured destruction" policy that kept the world on the brink of ruin during the Cold War, the United Nations' top nuclear controller said Thursday.

Even worse, Mohamed ElBaradei said, continued development of nuclear weapons puts the world at risk of realizing the condition foreseen by former President John F. Kennedy in the early 1960s of 20 to 30 nuclear powers.

"Efforts to control the spread of such weapons will only be delaying the inevitable — a world in which each country or group has laid claim to its own nuclear weapon. Mutually assured destruction will once again be the absurd hallmark of civilization at its technological peak," ElBaradei told the graduating class of Johns Hopkins University's Paul H. Nitze School of Advanced International Studies.

The concept that went by the macabre acronym MAD began in the 1950s and faded only after the breakup of the Soviet bloc beginning in the late 1980s. Its aim was to prevent nuclear annihilation through nuclear terror.

ElBaradei, who with his agency the International Atomic Energy Agency was awarded the 2005 Nobel Peace Prize for working against nuclear arms, said the only hope for avoiding a repetition of MAD is to change the world's idea of security.

"No one has seriously taken up the challenge of developing an alternative approach to security that eliminates the need for nuclear deterrence," he said.

"But only when such an alternative system is created will nuclear-weapon states begin moving toward nuclear disarmament. And only when nuclear-weapon states move away from depending on these weapons for their security will the threat of nuclear proliferation by other countries by meaningfully reduced."

A rearrangement of global priorities is in order, he said.

In 2004, he said the world spent more than $1 trillion (euro780 billion) on weapons and $80 billion (euro62.7 billion) on official development aid.

"Experts tell us that, for an additional $65 billion (euro51 billion) per year, we could cut world hunger in half, put programs in place for clean water worldwide, enable reproductive health care for women everywhere, eradicate illiteracy and provide immunization for every child," ElBaradei said.

Already, he said, "as an international community, we have no difficulties in cooperating when it comes to regulating shipping, coordinating the use of airwaves or jointly fighting epidemics.

"But when it comes to how to resolve our differences, our approach dates back to the Stone Age, still rooted primitively in who carries the biggest club."