Prime Minister Dr. Manmohan Singh left for Washington this morning to attend the Nuclear Security Summit being hosted by US President Obama on Monday and Tuesday. <br/><br/>The summit aims to enhance international co-operation to prevent nuclear terrorism, the most immediate threat to global security. <br/><br/>In his departure statement ahead of his visit to the United States and Brazil, the Prime Minister welcomed President Obama’s initiative to hold a summit on nuclear security. <br/><br/>Dr. Singh expects the summit to focus on nuclear terrorism and proliferation of sensitive nuclear materials and technologies. <br/><br/>He said India has been a consistent advocate of complete and universal global nuclear disarmament and is among the first countries in the world to call for a world-free of nuclear weapons. <br/><br/>AIR correspondent Sarita Brara reports from Washington that final touches were given to the summit documents where India was represented by Foreign Secretary Nirupama Rao. <br/> <br/>During his stay in Washington, the Prime Minister would have bilateral meetings with President Obama, President Nazarbaev of Kazakhstan, President Nicolas Sarkozy of France, Prime Minister Stephen Harper of Canada and other world leaders. <br/> <br/>After the Nuclear Security Summit, the Prime Minister would proceed to Brasilia to attend the fourth IBSA Summit and the second BRIC Summit, involving Russia, China and South Africa, besides the host Brazil. <br/><br/>These grouping reflect the growing role of emerging economies in shaping the global economic order. <br/> <br/>The Prime Minister would hold separate bilateral discussions with President Lula da Silva. Dr Singh would also have bilateral meetings with President Hu Jintao of China and President Dmitry Medvedev of Russia. <br/><br/>The meeting was chaired by US, Sherpa Gary Samore, Senior Advisor to the President and Senior Director for non-proliferation. Samore said there will be a high-level communique from the leaders which will recognise that nuclear terrorism is a serious threat. <br/><br/>He told reporters in a teleconference briefing that there will be a number of national actions that countries will announce in the context of the summit.<br/>