BEIJING, Feb. 28 Kyodo - The following is a chronology of major events related to nuclear issues involving North Korea.

March 12, 1993 -- North Korea says it will withdraw from the Nuclear Non-Proliferation Treaty (NPT).

Oct. 21, 1994 -- The United States and North Korea sign an accord in Geneva referred to as the Agreed Framework, which required Pyongyang to freeze and eventually dismantle its weapons-grade nuclear facilities in exchange for being provided with two light-water reactors for power generation.

March 9, 1995 -- The Korean Peninsula Energy Development Organization (KEDO), an international consortium tasked with providing the light-water reactors to North Korea, is launched.

Oct. 16, 2002 -- The U.S. says North Korea admitted to having a secret program to enrich uranium for nuclear weapons.

2003

Jan. 10 -- North Korea again says it will withdraw from the NPT.

Feb. 12 -- The International Atomic Energy Agency decides to refer the North Korean nuclear issue to the U.N. Security Council.

April 23-25 -- The U.S., North Korea and China hold talks in Beijing. North Korea tells U.S. it already has nuclear weapons.

Aug. 27-29 -- Six-nation talks involving China, Japan, North and South Korea, Russia and the U.S. take place in Beijing, but without significant progress.

Oct. 19 -- U.S. President George W. Bush says he will work toward providing an assurance in writing on North Korea's security through the six-nation framework.

Oct. 25 -- North Korea says it is ready to consider Bush's remarks on the security written assurance proposal.

Oct. 30 -- Top Chinese legislator Wu Bangguo and North Korean leader Kim Jong Il agree in principle to resume six-nation talks.

Nov. 4 -- KEDO decides to halt the project of building the light-water reactors.

Dec. 9 -- North Korea calls on the U.S. to give energy aid and lift sanctions in exchange for freezing its nuclear activities.

Dec. 25-27 -- North Korea agrees with China to hold the next round of six-nation talks during a meeting with Chinese Vice Foreign Minister Wang Yi.

2004

Jan. 6-10 -- U.S. nuclear experts visit North Korea to inspect nuclear facilities in Yongbyon.

Feb. 3 -- N. Korea and China announce the next round of six-nation talks to be held in Beijing.

Feb. 25-28 -- The second round of six-nation talks takes place in Beijing. No breakthrough on Pyongyang's nuclear programs. The six agree to hold the next round of talks in Beijing by the end of June, set up a working group and express their commitment to a ''nuclear-weapon-free Korean Peninsula.'' ==Kyodo