North Korea ordered U.N. inspectors to leave its Yongbyon complex on Tuesday, after saying it would quit international nuclear disarmament talks and restart the plant that makes bomb-grade plutonium, the United Nations said.
This is the third time the North has told nuclear inspectors to leave the Soviet-era plant that is the focal point of its nuclear arms program since inspections began in 2002.
Here is a timeline of international wrangling over Yongbyon.
* 1979: North Korea starts to build a 5-megawatt nuclear reactor at Yongbyon, aided by years of Soviet nuclear help.
* Dec 12, 1985: North Korea declares existence of the Yongbyon facility to the International Atomic Energy Agency as it joins the nuclear Non-Proliferation Treaty. The treaty requires IAEA inspectors to have regular access for monitoring.
* 1986: Yongbyon begins operation. Its main facilities are a nuclear fuel fabrication plant, the reactor and a facility to separate plutonium from spent nuclear fuel.
* July 1987: North Korea misses first 18-month deadline for the beginning of international inspections. Granted an 18-month extension, it also misses the second deadline in December 1988.
* May 1992: Inspections begin the IAEA says North Korea has processed more plutonium than it initially disclosed.
* March 1993: North Korea rejects IAEA inspectors' request to see two undeclared sites and threatens to withdraw from the NPT.
* June 1994: North Korea quits the IAEA, 20 years after it first became a member state.
* October 21: U.S. President Bill Clinton's administration signs an Agreed Framework with North Korea to freeze its nuclear program in exchange for aid.
* Dec 12, 2002: North Korea says it plans to restart Yongbyon reactor. By the end of the month it has disabled the IAEA surveillance devices there and expels the agency's inspectors.
The move comes two months after U.S. State Department envoy James Kelly confronts Pyongyang with evidence Washington says points to a covert uranium enrichment program.
* January 2003: North Korea quits the NPT.
* Sept 2005: North reaches deal with China, Japan, Russia, South Korea and United States on "abandoning all nuclear weapons and existing nuclear programs and returning, at an early date, to the NPT and to IAEA safeguards" at talks in Beijing.
* Oct 9, 2006: North carries out first nuclear test.
* February 13, 2007: North Korea agrees to start shutting its reactor and allow U.N. nuclear inspectors back into country in exchange for aid, the first step in a new disarmament deal.
* July 14-18: IAEA team confirms shutdown of five nuclear facilities in Yongbyon. It applies seals, and starts installing surveillance and monitoring equipment.
* June 27, 2008: DPRK demolishes cooling tower at Yongbyon nuclear reactor, as a sign of good faith in negotiations.
* August 26: Pyongyang says it will reverse disablement of Yongbyon facilities, angered by a Washington decision not to take it off its terrorism blacklist.
* Sept: North Korea makes minor initial moves to restart the plant, U.S. and South Korean officials say. On Oct 9, the IAEA says DPRK will no longer give its inspectors access to Yongbyon.
* Oct 11: U.S. says it will take North Korea off state sponsors of terrorism list, following verbal agreement on dismantlement. North says next day to resume disablement. IAEA soon granted access to key Yongbyon plants
* April 5, 2009: North Korea launches a multistage rocket. A week later, on the 13th, the U.N. security council adopts a declaration condemning North Korea for the launch.
* April 14: North Korea's foreign ministry says the country will six-part quit talks, and re-start Yongbyon plant that makes arms-grade plutonium. It orders U.N. inspectors to leave.
Sources: Reuters, IAEA (here and here)
(Writing by Gillian Murdoch; Editing by David Fox)