Key dates in talks aimed at ending the standoff over North Korea's nuclear weapons drive:
1994
North Korea and the US sign a nuclear safeguard accord after Pyongyang vows to freeze and eventually dismantle its nuclear weapons program.
2002
October: North Korea reportedly admits to US special envoy James Kelly that it is running a uranium enrichment program in violation of the 1994 accord.
2003
Jan 10: Pyongyang withdraws from the nuclear Non-Proliferation Treaty (NPT).
April 23: The United States, North Korea and China meet for three days of talks in Beijing. North Korea admits to possessing nuclear weapons, according to the US side. Pyongyang submits a "bold proposal" for resolving the crisis.
Aug 27-29: South Korea, Russia and Japan join the first round of six-way nuclear talks in Beijing. North Korea threatens to conduct a nuclear test and declare itself a nuclear power.
Oct 2: North Korea says it has produced enough weapons-grade plutonium for half-a-dozen atomic bombs as a step towards boosting its nuclear deterrent. Two weeks later it vows to display the "physical force" of its nuclear deterrent.
2004
Jan 12: North Korea again offers to freeze nuclear reactors producing weapons grade plutonium if compensated by Washington.
Feb 22-24: Second round of six-party talks end without progress. China says "severe" differences remain.
May 14: North Korea says it will never accept US demands for a complete dismantling of its nuclear programs at working level six-nation talks in Beijing.
June 23-25: Third round of six-party talks held in Beijing. No progress reported but parties agree to meet again for a fourth round in September.
Aug 23: North Korea says it is "impossible" to attend more talks because of "hostile" US policy, labels Bush an "imbecile" and a "tyrant" who is worse than Adolf Hitler.
Sept 28: The US warns North Korea it might be reported to the UN Security Council if it refuses participation in six-party talks.
Oct 8: North Korea says it is ready to resume six-party talks at any time and blames the delay on Bush for stalling.
Dec 4: North Korea says it will not return to talks until the lineup of a new US administration emerges.
2005
Feb 10: North Korea indefinitely suspends participation in talks and says it has manufactured nuclear weapons.
March 16: North Korea lashes out at US Secretary of State Condoleezza Rice for calling the communist state an "outpost of tyranny" and rules out new talks.
March 31: North Korea says the six-party talks should be transformed into arms reduction talks, as it has already produced nuclear weapons.
May 5: The International Atomic Energy Agency estimates that North Korea has close to six nuclear weapons.
May 13: US and North Korean officials meet in New York.
June 6: US and North Korean officials meet again in New York.
June 7: North Korea will return to six nation talks on its nuclear arms programme within "weeks", China's ambassador to the United Nations says.
June 8: North Korea says no nuclear talks unless Washington meets unspecified conditions.
