The head of the UN nuclear watchdog says North Korea, and not Iran, is the biggest proliferation threat facing the world at the moment.

International Atomic Energy Agency (IAEA) chief Mohamed ElBaradei made the remarks Tuesday during a meeting of NATO parliamentarians in Slovakia.

ElBaradei said North Korea's nuclear ambitions comprise the most serious situation the international community is facing right now and warned against sending the message out of North Korea that in his words "if you really want to protect yourself...the best way is to accelerate the building of a nuclear defense." He said such a message would be the worst signal the international community could send.

He also said that the way the North's nuclear issue is handled will be a very important precedent for how the international community will deal with cases of non-compliance.

Meanwhile, ElBaradei also said IAEA inspectors had found no clear proof of a military dimension to Iran's atomic program, which the United States says is a front for developing a nuclear bomb.

North Korea expelled IAEA inspectors and withdrew from the Non- Proliferation Treaty last year. The United States believes it has at least one nuclear weapon already.