CHRONOLOGY: Obama's hectic 'nuclear' spring

Apr 7, 2010, 6:54 GMT

Washington - US President Barack Obama is juggling an intense array of events this spring aimed at making the world less susceptible to nuclear terrorism and war.

Keeping the events straight is a challenge even for Washington insiders. But for Obama, the sequence of agreements, signings, summits and reviews are all part of a grand plan he laid out in 2008 as he was running for the US presidency.

April 5, 2009 - Obama outlines his vision of a nuclear-free world in Prague. The Nobel Peace Prize committee is impressed enough to give him the prize months later despite US involvement in two wars.

March 26, 2010 - Russia and US announce agreement to drastically reduce nuclear arsenals: The New START (Strategic Arms Reduction Treaty) replaces an earlier START that expired in December 2009.

April 6, 2010 - Obama alters US nuclear policy in his congressionally mandated Nuclear Posture Review. The US pledges to never use nuclear weapons against states that comply with non- proliferation treaties, but reserves the right to strike first with a nuclear attack.

April 8, 2010 - Obama and Russian President Dmitry Medvedev to meet in Prague to sign the START agreement, pledging to reduce their nuclear warheads to 1,550, or about one-third below current levels.

April 12-13, 2010 - Obama to host Washington summit of 47 countries on keeping nuclear materials used in weapons and other fields out of the hands of terrorists and rogue criminals. Obama has in mind an ambitious four-year programme to secure all vulnerable nuclear materials. The summit could strengthen the 2003 Proliferation Security Initiative, where more than 90 countries cooperate voluntarily to intercept illicit shipments.

May 3-28, 2010 - United Nation's five-year review in New York of the Nonproliferation Treaty (NPT). Obama wants to strengthen the NPT, using the leverage gained through his other efforts. But the prospects are challenging. Already, three non-members - India, Pakistan and North Korea - have openly exploded atomic bombs and Israel has kept a cloak of secrecy over its own programme. Obama is pushing for a new round of UN sanctions to keep Iran from becoming a nuclear power, a push that could be a central element of the review.