WASHINGTON (Yonhap News) ― North Korea was placed at the bottom of a landmark ranking Wednesday on the security of nuclear materials.

The report was released by a group of experts here working to curb the threat of nuclear terrorism and accidents.

The unprecedented Nuclear Materials Security Index, compiled by the Nuclear Threat Initiative in Washington, examined the status of nuclear materials security conditions in 176 countries.

It was issued ahead of the Nuclear Security Summit in Seoul in March.

In the survey of 32 nations with one kilogram or more of weapons-grade uranium or plutonium, North Korea ranked 32nd. The index took into account the amount of nuclear materials, sites, domestic commitments, societal factors, and global norms. Iran and Pakistan ranked 30th and 31st, respectively.

In 2008, during talks with the U.S., the secretive North reportedly declared that it possessed roughly 38.5 kg of plutonium.

The NTI said it demanded that North Korean authorities verify information jointly collected with the Economist Intelligence Unit, but Pyongyang said no.

In an interview with Yonhap News Agency, former U.S. Sen. Sam Nunn of Georgia, who co-founded the NTI, called for broader efforts to foil possible nuclear terrorism and resolve the North Korean nuclear issue.

“This index is really our effort to inspire governments around the world to understand the importance of nuclear materials security, making sure that we prevent catastrophic terrorism,” he said.

Nunn is well known for introducing legislation, along with Sen. Richard Lugar of Indiana, to aid Russia in reducing its nuclear arsenal after the Cold War.

He said the upcoming Seoul summit is a “great opportunity to have dialogue and discussion about the priorities for securing nuclear material” that could fall into the hands of terrorists.

He also held out expectations for North Korea’s new leadership and the resumption of talks.

“Dialogue, that kind of discussion, six-party talks, at some point have to resume,” he said. “In the meantime, countries have to have a lot more confidence-building measures, and some of the incidents and acts that have come from North Korea have been very disruptive to that process.”

He said there is a chance now for North Korea to change course as the world takes a fresh look at Pyongyang.

“I think we will certainly leave that possibility open,” he said.