04 April 2016 Current Affairs: The 2016 Nuclear Security Summit concluded on 1 April 2016 at the Walter E. Washington Convention Center, Washington, D.C., United States.The fourth edition of the conference, which commenced on 31 March 2016, succeeded the 2014 Nuclear Security Summit. The summit was organised by the Nuclear Energy Institute (NEI).The summit was attended by over 50 World leaders, including Prime Minister Narendra Modi. At the summit, the world leaders pledged to reduce nuclear stocks and protect the active inventories from falling into the hands of terrorists, which could prove to be catastrophic. However, leaders or representatives of Russia, North Korea, Iran and Belarus remained absent from the summit.Key announcements made at the NSS 2016 : Many countries, including Kazakhstan and Poland, agreed to to reduce their highly-enriched uranium stockpiles.Japan undertook to ship additional separated plutonium to the U.S.Canada pledged 42 million US dollars to bolster nuclear security.The U.S. disclosed that its own inventory of highly enriched uranium has dropped from 741 metric tons in the 1990s to 586 metric tons as of 2013.According to the U.S., since the last summit in 2014, 10 nations have removed or disposed of about 450 kilograms of highly enriched uranium.Argentina, Switzerland and Uzbekistan are now free of highly enriched uranium, as is all of Latin America and the Caribbean. About Nuclear Security Summit : The Nuclear Security Summit is a world summit, aimed at preventing nuclear terrorism around the globe.The genesis of the NSS lies in the speech given by the US president Barrack Obama in Prague, Czech Republic in 2009. In this speech, President Obama called for establishment of nuclear security architecture to prevent the threat of nuclear terrorism.The first summit was held in Washington, D.C., United States from 12 April to 13 April 2010.The second summit was held in Seoul, South Korea, in 2012.The third summit was held in The Hague, Netherlands, from 24 March to 25 March 2014.