Thirty-five countries at the Nuclear Security Summit at The Hague have pledged to put international nuclear security guidelines into their national laws.
The countries agreed to the initiative on March 25, although 18 countries -- including nuclear powers Russia, China, India, and Pakistan -- declined to sign it.
The deal also obligates countries to allow independent reviews of their security procedures in steps aimed at keeping nuclear material out of the hands of terrorists.
U.S. Energy Secretary Ernest Moniz said the regulations in the initiative are "the closest things we have to international standards for nuclear security."
Since the NSS was launched by U.S. President Barack Obama in 2010, the number of countries that have enough nuclear material to build atomic weapons has decreased from 39 four years ago to 25 today.
Based on reporting by AFP and AP