Israel came close to the bottom of a new survey examining the security conditions of nuclear materials held in 32 different countries.

Israel ranked 25th in the study, published by the Nuclear Threat Initiative, scoring 56 out of 100.

Australia was given the highest overall grade on the list of "countries with weapons-usable nuclear materials." The study deemed Britain the most secure of the countries with nuclear weapons - a group the researchers say includes Israel - followed by the United States. The list concludes with North Korea; Pakistan and Iran are just above it, the latter receiving an overall score of 46.

In response, the Israel Atomic Energy Commission said Israel's nuclear policy is known internationally to be responsible, restrained and under supervision by the government, Knesset and the state comptroller.

The Nuclear Threat Initiative's report was timed to coincide with the Nuclear Security Summit to be held in late March in Seoul, South Korea. The organizers have invited Prime Minister Benjamin Netanyahu to the conference. No official response has been made but Netanyahu reportedly intends to send Intelligence and Atomic Energy Minister Dan Meridor. However, Meridor is not in charge of the Atomic Energy Commission; the head of that body, Shaul Horev, reports directly to Netanyahu.

The study rates each country according to five criteria: quantities and sites, security and control measures, global norms, domestic commitments and capacity, and societal factors.

Israel scored its highest average grade, 78, in security and control measures, which included 100s for security personnel measures, physical security during transportation and independent regulatory agency.

However, Israel was given low marks on pervasiveness of corruption, legislation and quantities of nuclear material.

It was ranked last when it came to nuclear security transparency and procedures for control and accounting procedures. The researchers were convinced that such procedures existed, but the official secrecy around them necessarily worked against Israel.

Yael Doron, spokeswoman for the Nuclear Energy Commission, said yesterday that Israel is perceived both internationally and in the region as having a "responsible and restrained policy."

Doron said Israel conducted itself "in keeping with its character and democratic values. Israel is a member of the International Atomic Energy Agency in Vienna. The level of nuclear security and safety has been set by strict international standards. Israel also plays its part in nuclear nonproliferation and the Atomic Energy Commission services as a professional guide to the bodies responsible for monitoring this in Israel."

She added that the licensing unit in the Atomic Energy Commission was an independent body and that it was monitored by an independent unit on nuclear security that reported from time to time on the state of Israel's nuclear security to the prime minister.