The 4th Nuclear Security Summit will begin in Washington DC today. Heads of about 50 countries and representatives of five international organisations have started to arrive in Washington to take part in summit to discuss a gamut of issues pertaining to nuclear security. <br/><br/>The two-day summit will highlight achievements and commitments of several countries towards safeguarding nuclear devices and technologies and reducing the threat of nuclear terrorism. <br/><br/>Prime Minister Narendra Modi has left for Washington to participate in the Global Nuclear Security Summit after wrapping up his visit to the Belgian capital Brussels. <br/><br/>Mr Modi is expected to reiterate India's commitment to nuclear safety and disarmament.<br/><br/>Talking to AIR, Indian Ambassador to US, Arun K Singh said that India has been contributing its bit to strengthen nuclear security by taking an active part in the summit ever since its inception in 2010. <br/><br/>The Ambassador said that the summit will begin with global leaders meeting at White House this evening to discuss nuclear threat perceptions. President Barack Obama will host a working dinner for the delegates on the occasion. The Indian ambassador said the summit will have three working sessions tomorrow including one on nuclear terrorism.