Here is a chronology of nuclear tests since the Non-Proliferation Treaty (NPT) was made permanent in 1995. 1995 May 11 Many nations agree to make permanent the 25-year-old Non-Proliferation Treaty (NPT) on stopping the spread of nuclear weapons. A U.N. conference publicly approves indefinite extension of the 178-member agreement. May 15 China conducts an underground nuclear test just days after the successful extension of the NPT treaty. June 13 President Jacques Chirac announces France will resume nuclear weapons testing at its South Pacific site in September, setting off widespread protests throughout the area. August 6 Hiroshima commemorates 50th anniversary of atomic bombing by the United States. August 17 China's second underground nuclear test in five months provokes a world-wide storm of condemnation. September 5 France conducts underground nuclear test on Mururoa Atoll, bringing worldwide condemnation and riot in Tahiti. September 22 International Court of Justice in Hague rejects New Zealand bid to stop further French testing in South Pacific. October 1 France conducts second blast of series at Fangataufa atoll, more than five times as powerful as the first. Sixteen-nation South Pacific Forum suspends ties with Paris. French commandos seize Greenpeace ship Manuatea in international waters off Mururoa. October 27 France sets off third nuclear explosion equivalent to under 60 kilotonnes of TNT. November 21 France carries out fourth test at Mururoa, equivalent to less than 40 kilotonnes of TNT. December 27 France stages fifth test at Mururoa, equivalent to less than 30 kilotonnes of TNT. 1996 January 27 France conducts sixth and most powerful test at Fangataufa, equivalent to under 120 kilotonnes of TNT. January 29 Chirac announces an end to French nuclear tests. March 25 France, Britain and the United States sign South Pacific Nuclear Free Zone Treaty. April 11 Forty-three African states sign treaty declaring Africa free of nuclear weapons. June 8 China carried out a nuclear explosion at the Lop Nor test site in northwestern Xinjiang province. September 11 United Nations approves Comprehensive Test Ban Treaty (CTBT), which bans nuclear test explosions but not laboratory testing to refine nuclear weapons. India rejects treaty as flawed; Pakistan says it will not sign unless India does first. 1997 July 2 United States begins a round of controversial underground nuclear weapons related tests in the Nevada desert. September 18 The United States conducts a second underground explosive test on radioactive plutonium at a Nevada site. 1998 February 24 France's National Assembly votes unanimously to ratify CTBT. March 19 The U.S. Department of Energy announces it will begin a series of underground explosive tests on radioactive plutonium later in the month. May 11 India conducts three underground nuclear tests in the Thar desert in the state of Rajasthan, close to India's border with Pakistan.