Nearly 4 kilograms (9 pounds) of highly enriched uranium has been returned to Russia from Vietnam under a Russian-American program to secure nuclear materials that could be used to make weapons, the Rosatom nuclear agency said Monday, according to AP. The transfer of 3.9 kilograms (8.6 pounds) of uranium from a research reactor in the Vietnamese city of Dalat was completed Saturday, Rosatom said. It was conducted with help of the International Atomic Energy Agency, the U.N. nuclear watchdog. The transfer took place under a Russian-American program under which Russian-produced highly enriched fuel located in formerly Soviet-allied countries is sent back to be blended down to a concentration that no longer would be suitable for making a weapon. More than 500 kilograms (1,102 pounds) of highly enriched uranium has been returned under the program since 2002, Rosatom said. Previous shipments have come from countries including Libya, Serbia, Bulgaria and the Czech Republic. The fuel from Vietnam will be converted into low-enriched nuclear material, the agency said. It said low-enriched nuclear fuel produced at a Siberian plant was delivered to the research reactor in Dalat.