Timeline: North Korea's nuclear weapons development
A satellite photo shows North Korea's suspected nuclear facility at Yongbyon.
Chronology of nuclear weapons development in North Korea:
1993: North Korea says it has quit the Nuclear Nonproliferation Treaty amid suspicions that it is developing nuclear weapons. It later reverses that decision.
1994: North Korea and U.S. sign an agreement. North Korea pledges to freeze and eventually dismantle its nuclear weapons program in exchange for international aid to build two power-producing nuclear reactors.
Aug. 31, 1998: North Korea fires a multistage over Japan and into the Pacific Ocean, proving it can strike any part of Japan's territory.
May 25-28, 1999: Former Defense Secretary William Perry visits North Korea and delivers a U.S. disarmament proposal.
Sept. 13: North Korea pledges to freeze long-range missile tests.
Sept. 17: U.S. President Bill Clinton eases economic sanctions against North Korea.
December: A U.S.-led consortium signs a US$4.6 billion contract for two safer, Western-developed light-water nuclear reactors in North Korea.
July 2000: North Korea again threatens to restart its nuclear program if Washington doesn't compensate for the loss of electricity caused by delays in building nuclear power plants.
June 2001: North Korea warns it will reconsider its moratorium on missile tests if the Bush administration doesn't resume contacts aimed at normalizing relations.
July: State Department reports North Korea is going ahead with development of its long-range missile. A Bush administration official says North Korea conducts an engine test of the Taepodong-1 missile.
December: President Bush warns Iraq and North Korea that they would be "held accountable" if they developed weapons of mass destruction "that will be used to terrorize nations."
Jan. 29, 2002: Bush labels North Korea, Iran and Iraq an "axis of evil" in his State of the Union address. "By seeking weapons of mass destruction, these regimes pose a grave and growing danger," he says.
Oct. 4: A visiting U.S. delegation says North Korean officials revealed that the country has a second covert nuclear weapons program in violation of the 1994 agreement -- a program using enriched uranium. North Korea later denies this.
Oct. 16: U.S. officials say they have discovered evidence of a nuclear weapons program in North Korea.
Oct. 26: Bush, Japanese Prime Minister Junichiro Koizumi and South Korean President Kim Dae-jung meet at an Asian-Pacific regional summit in Mexico and agree to seek a peaceful end to the North's nuclear problem.
Nov. 11: The United States, Japan and South Korea halt oil supplies to North Korea promised under the 1994 deal.
Dec. 12: North Korea reactivates nuclear facilities at Yongbyon that were frozen under the 1994 deal with the United States.
Dec. 13: North Korea asks the U.N. nuclear watchdog to remove monitoring seals and cameras from its nuclear facilities.
Dec. 14: The U.N. International Atomic Energy Agency urges North Korea to retract its decision to reactivate its nuclear facilities and abide by its obligations under the Nuclear Nonproliferation Treaty.
Dec. 21: North Korea removes monitoring seals and cameras from its nuclear facilities
Jan. 10, 2003: North Korea withdraws from the Nuclear Nonproliferation Treaty.
Jan. 28: South Korean envoy Lim Dong-won meets North Korea's number two leader Kim Yong Nam. Lim says North Korean leader Kim Jong Il has received the letter from President Kim Dae-jung that suggests Pyongyang should reverse its withdrawal from the Nuclear Non-Proliferation Treaty.
Feb. 3: The U.S. Defense Secretary Donald Rumsfeld signs a "prepare to deploy" order that will send 24 bombers to the Pacific region.
Feb 4: Pyongyang describes the U.S. move as an attempt "to crush us to death."
Feb. 5: North Korea's official news agency says the nation has reactivated its nuclear power facilities.
Feb. 12: The 35-member IAEA board of governors declares North Korea in breach of atomic safeguards and refers the case to the U.N. Security Council.
Feb. 18: The (North) Korean People's Army threatens it will abandon the 1953 Korean War armistice if the United States continues its military buildup in the region.
Feb. 24: North Korea test fires a land-to-ship missile into the sea between the Korean Peninsula and Japan.
Feb. 26: The United States says North Korea has reactivated its five-megawatt nuclear reactor at Yongbyon.
March 10: North Korea test fires another surface-to-vessel anti-ship missile into the Sea of Japan, or East Sea as it is known in South Korea.
March 29: Pyongyang says it will resist all international demands to allow nuclear inspections.
April 5: North Korea says it won't recognize any ruling made by the U.N. Security Council.
April 12: In a dramatic shift, North Korea backtracks on its calls for direct 'face-to- face' talks with Washington, saying it will consider any format for dialogue if the United States is prepared to make a "bold switchover."
June 2: Group of Eight world leaders meeting in France accuses North Korea of undermining non-proliferation agreements.
June 9: North Korea lifts its war of words with the United States to a new level, saying it may now need nuclear weapons to combat what it describes as a hostile threat from Washington.
July 12: A senior U.S. official says North Korea has begun reprocessing spent nuclear fuel rods, suggesting the communist country intends to produce nuclear weapons.
July 16: China ups the pressure on North Korea to join mulitlateral talks to end the nuclear standoff during a visit to Pyongyang by a special envoy from Beijing. "In-depth" talks take place.
July 26: A Japanese newspaper report, citing North Korean and Japanese sources, says North Korea is prepared to conduct a nuclear test unless the U.S. responds positively to its proposals to end the nuclear row.
August 1: North Korea announces it will take part in six-nation talks on the crisis. No date or venue for the meet is set.
August 2: Pyongyang warns the United States not to discuss its suspected nuclear weapons program at the U.N. Such a move would be "a grave criminal act" that was "little short of a prelude to war," Pyongyang says.
August 12: Washington announces that six-way talks aimed at ending the crisis will take place in Beijing on August 27. The U.S., North Korea, South Korea, China, Japan and Russia will take part.
August 18: North Korea repeats a demand that Washington sign a non-aggression pact with North Korea, and says it could not dismantle its nuclear deterrent force if the United States did not abandon its "hostile policy" toward Pyongyang.