(FILES) In this file photo taken on March 12, 2017 a man carries fake nuclear barrels during a demonstration to demand the closure of Fessenheim nuclear power plant in Fessenheim, eastern France. The Nuclear Nonproliferation Treaty (NPT), signed in 1968 by 191 countries, commits the five official holders of the atomic bomb (United States, Russia, France, Britain and China) to not transfer military nuclear technology to other countries, and prohibits non-nuclear countries from procuring or manufacturing nuclear weapons. / AFP PHOTO / SEBASTIEN BOZON