2 May 2013 Last updated at 11:50 ET

North Korea profile

• Overview
• Facts
• Leaders
• Media
• Timeline

A chronology of key events:

1945 - After World War II, Japanese occupation of Korea ends with Soviet troops occupying the north, and US troops the south.

1946 - North Korea's Communist Party (Korean Workers' Party - KWP) inaugurated. Soviet-backed leadership installed, including Red Army-trained Kim Il-sung.

1948 - Democratic People's Republic of Korea proclaimed. Soviet troops withdraw.

1950 - South declares independence, sparking North Korean invasion.

1953 - Armistice ends Korean War, which has cost two million lives.

1960s - Rapid industrial growth.

1968 - US intelligence-gathering vessel seized by North Korean gunboats.

1969 - US reconnaissance plane shot down.

1972 - After secret North-South talks, both sides seek to develop

1980 - Kim Il-sung's son, Kim Jong-il, moves up party and political ladder.

1991 - North and South Korea join the United Nations.

1992 - North Korea agrees to allow inspections by International Atomic Energy Agency (IAEA), but over next two years refuses access to sites of suspected nuclear weapons production.

1994 - Death of Kim Il-sung. Kim Jong-il succeeds him as leader, but doesn't take presidential title. North Korea agrees to freeze nuclear programme in return for $5bn worth of free fuel and two nuclear reactors.

1995 - US formally agrees to help provide two modern nuclear reactors designed to produce less weapons-grade plutonium.

Flood and famine

1996 - Severe famine follows widespread floods.

Pyongyang announces it will no longer abide by the armistice that ended the Korean War, and sends troops into the demilitarised zone.

North Korean submarine runs aground in South.

1998 - The late Kim Il-song declared "eternal president", while Kim Jong-il's powers widened to encompass head of state.

UN food aid brought in to help famine victims.

North launches rocket which flies over Japan and lands in the Pacific Ocean. Pyongyang insists it fired a satellite, not a missile.

South Korea captures North Korean mini-submarine in its waters. Crew inside found dead.

Historic handshake

2000 - Summit in Pyongyang between Kim Jong-il and South Korean President Kim Dae-jung. North stops propaganda broadcasts against the South.

Senior journalists from South Korea visit the North to open up communication.

Reopening of border liaison offices at the truce village of Panmunjom, in the no-man's-land between the heavily fortified borders of the two countries.

South Korea gives amnesty to more than 3,500 prisoners.

One hundred North Koreans meet their relatives in the South in a highly-charged, emotional reunion.

2001 May - A European Union delegation headed by Swedish Prime Minister Goran Persson visits to help shore up the fragile reconciliation process with South Korea. The group represents the highest-level Western diplomatic mission ever to travel to North Korea.

2001 June - North Korea says it is grappling with the worst spring drought of its history.

2001 August - Kim Jong Il arrives for his first visit to Moscow after an epic nine-day, 10,000-kilometre train journey from Pyongyang. Kim apparently dislikes flying.

2002 January - US President George W Bush says North Korea is part of an "axis of evil", along with states such as Iraq and Iran. Pyongyang says Mr Bush has not stopped far short of declaring war.

2002 June - North and South Korean naval vessels wage a gun battle in the Yellow Sea, the worst skirmish for three years. Some 30 North Korean and four South Korean sailors are killed.

2002 September - Japanese Prime Minister Junichiro Koizumi visits, the first Japanese leader to do so. He meets Kim Jong-il who apologises for the abductions of Japanese citizens in the 1970s and 1980s.

Nuclear brinkmanship

2002 October-December - Nuclear tensions mount. In October the US says North Korea has admitted to having a secret weapons programme. The US decides to halt oil shipments to Pyongyang. In December North Korea begins to reactivate its Yongbyon reactor. International inspectors are thrown out.

2003 January - North Korea withdraws from the Nuclear Non-Proliferation Treaty (NPT), a key international agreement aimed at preventing the spread of atomic weapons.

2003 April - Delegations from North Korea, the US and China begin talks in Beijing on North Korea's nuclear ambitions, the first such discussions since the start of the nuclear crisis.

2003 July - Pyongyang says it has enough plutonium to start making nuclear bombs.

Six-nation talks

2003 August - Six-nation talks in Beijing on North Korea's nuclear programme fail to bridge gap between Washington and Pyongyang.

2003 October - Pyongyang says it has reprocessed 8,000 nuclear fuel rods, obtaining enough material to make up to six nuclear bombs.

2004 April - More than 160 killed and hundreds more injured when train carrying oil and chemicals hits power line in town of Ryongchon.

2004 June - Third round of six-nation talks on nuclear programme ends inconclusively. North Korea pulls out of scheduled September round.

2004 December - Row with Japan over fate of Japanese citizens kidnapped and trained as spies by North Korea in 70s, 80s. Tokyo says eight victims, said by Pyongyang to be dead, are alive.

2005 February - Pyongyang says it has built nuclear weapons for self-defence.

2005 September - Fourth round of six-nation talks on nuclear programme concludes. North Korea agrees to give up its weapons in return for aid and security guarantees. But it later demands a civilian nuclear reactor.

2006 February - High-level talks with Japan, the first since 2003, fail to yield agreement on key issues, including the fate of Japanese citizens abducted by North Korea.

2006 July - North Korea test-fires a long-range missile, and some medium-range ones, to an international outcry. Despite reportedly having the capability to hit the US, the long-range Taepodong-2 crashes shortly after take-off, US officials say.

2006 October - North Korea claims to test a nuclear weapon for the first time.

2007 February - Six-nation talks on nuclear programme resume in Beijing. In a last-minute deal, North Korea agrees to close its main nuclear reactor in exchange for fuel aid.

2007 May - Passenger trains cross the North-South border for the first time in 56 years.

2007 June - International Atomic Energy Agency inspectors visit the Yongbyon nuclear complex for the first time since being expelled in 2002. In July, they verify the shutdown of the Yongbyon reactor.

2007 August - North Korea appeals for aid after devastating floods.

Nuclear declaration

2007 October - Pyongyang commits to disable three nuclear facilities and declare all its nuclear programmes by year-end.

The presidents of North and South Korea pledge at a Pyongyang summit to seek talks to formally end the Korean war.

2007 November - North and South Korea's prime ministers meet for the first time in 15 years.

2008 February - The New York Philharmonic performs a groundbreaking concert in Pyongyang - a move seen as an act of cultural diplomacy.

2008 February - South Korea's new conservative President Lee Myung-bak says aid to North conditional on nuclear disarmament and human rights progress.

2008 March-April - North-South relations deteriorate sharply. North Korea expels Southern managers from joint industrial base, test-fires short-range missiles and accuses President Lee Myung-bak of sending a warship into Northern waters.

2008 June - In what is seen as a key step in the denuclearisation process, North Korea makes its long-awaited declaration of its nuclear assets.

2008 July - Soldier shoots South Korean woman in the Mount Kumgang special tourism area of North Korea, prompting further tensions.

Foreign Minister Pak Ui-chun and US Secretary of State Condoleezza Rice hold talks on Pyongyang's nuclear disarmament, the first such meeting for four years.

2008 September - North Korea accuses the US of not fulfilling its part of a disarmament-for-aid deal and says it is preparing to restart the Yongbyon reactor.

2008 October - The US removes North Korea from its list of countries which sponsor terrorism, in return for Pyongyang agreeing to provide full access to its nuclear sites.

2008 November - North Korea says it will cut off all overland travel to and from the South from December, and blames South Korea for pursuing a confrontational policy.

2008 December - Pyongyang says it will slow down work to dismantle its nuclear programme in response to a US decision to suspend energy aid. The US move came following the breakdown of international talks to end the country's nuclear activities.

Nuclear tensions rise

2009 January - North Korea says it is scrapping all military and political deals with the South, accusing Seoul of "hostile intent".

2009 April - North Korea launches a rocket carrying what it says is a communications satellite; its neighbours accuse it of testing long-range missile technology. After criticism from the UN Security Council, North Korea walks out of international six-party talks aimed at winding up its nuclear programme.

Kim Jong-il attends parliamentary vote to re-elect him leader, in his first major state appearance since a suspected stroke in 2008.

2009 May - North Korea says it successfully carries out an underground nuclear test, its second ever, drawing protests from the US, China and Russia.

It also announces that it no longer considers itself bound by the terms of the 1953 truce that ended the war between the two Koreas.

Defence Secretary Robert Gates says US "will not accept" a nuclear-armed North Korea.

2009 June - North Korea sentences US journalists Laura Ling and Euna Lee to 12 years hard labour for allegedly crossing the border illegally. They are freed in August, after former US President Bill Clinton visits to help secure their release.

UN Security Council votes unanimously to impose tougher sanctions. Pyongyang responds by saying it will view any US-led attempt to blockade the country as an "act of war" and that it plans to "weaponise" its plutonium stocks.

Tensions subside

2009 August - Pyongyang makes conciliatory gestures to Seoul. It sends a delegation to the funeral of former South Korean President Kim Dae-jung, frees four South Korean fishermen, and agrees to resume programme of family reunions.

2009 November - North Korea launches a confiscatory currency reform that causes disruption to private markets and unprecedented public protests into the New Year.

2009 December - US envoy Stephen Bosworth visits Pyongyang, reaches "common understanding" on need to resume six-nation talks on nuclear programme. In January, North Korea calls for an end to hostile relations with US and vows to strive for a nuclear-free Korean peninsula.

2010 February - The government reportedly eases restrictions on private markets after the currency revaluation of 2009 wiped out many cash savings.

Sinking of Cheonan

2010 March - Sinking of South Korean warship Cheonan, allegedly by the North, raises tensions to new heights.

2010 July - United States announces new sanctions on North Korea in response to sinking of Cheonan warship.

2010 September - As US President Obama signs new sanctions into law, the North makes overtures to the South, including an offer of more family reunions and acceptance of flood-damage aid.

Kim Jong-il's youngest son Kim Jong-un is appointed to senior political and military posts, fuelling speculation that he is being prepared to succeed his father.

2010 November - North Korea shows an eminent visiting American nuclear scientist a vast new secretly-built facility for enriching uranium at its Yongbyon complex. The revelation sparks alarm and anger in Washington, Seoul and Tokyo.

Cross-border clash near disputed maritime border results in death of two South Korean marines. North Korea's military insists it did not open fire first and blames South Korea for the incident.

2011 February - Foot and mouth disease hits livestock, threatening to aggravate desperate food shortages.

Succession

2011 December - Kim Jong-il dies. Kim Jong-un presides at his funeral, is hailed as "Great Successor" and takes over from his father as chairman of the National Defence Commission.

2012 February - Kim Jong-il is posthumously awarded the highest military title of Generalissimo - the same rank held by his father, Kim Il-sung.

Army pledges loyalty to his successor, Kim Jong-un, in a mass parade held to mark the 70th anniversary of Kim Jong-il's birth.

2012 April - Kim Jong-un formally takes over ruling party leadership, becoming First Secretary of the Workers Party.

The launch of a "rocket-mounted satellite" to mark the birthday of Kim Il-Sung fails. Most observers think it was a long-range missile test of the sort that North Korea had agreed to suspend in return for US food aid. North Korea says it is no longer bound by the agreement, which also banned nuclear tests.

2012 July - Army head Ri Yong-ho is removed from senior posts in the ruling party, and leader Kim Jong-un appoints himself to the highest rank of marshal.

2012 August - The United Nations says North Korea has asked for urgent food aid after devastating floods in July.

2012 October - Days after South Korea and the US unveil a new missile deal, North Korea says it has missiles that can hit the US mainland.

2012 December - A North Korean rocket launch puts a satellite into orbit, after the failure to do so in April. The UN including China regard this as a violation of a ban on North Korean ballistic missile tests, as the rocket technology is the same.

Third nuclear test

2013 January - The UN Security Council condemns the December launch. North Korea announces it will carry out a third "high-level nuclear test" and rehearse more long-range rocket launches aimed at the US "arch-enemy". The previous two tests were conducted in 2006 and 2009.

2013 February - North Korea carries out a third nuclear test, said to be twice as big as the 2009 test.

2013 March - UN Security Council approves fresh sanctions over North Korea's nuclear test, targeting cash transfers and travel for diplomats. North Koreas threatened the US with a pre-emptive nuclear attack and issues threats to South Korea over nearby islands and non-aggression pacts.

2013 April - North Korea says it will restart all facilities at its main Yongbyon nuclear complex and withdraws its workers from the South-Korean-funded Kaesong joint industrial park. It also warns foreigners to leave both North and South Korea to avoid the threat of war.

It later offers talks to reduce tension if UN sanctions are lifted and the US and South Korea end joint military drills. South Korea rejects the proposals as "incomprehensible".

2013 May - North Korea sentences a US citizen, Pae Jun-ho - known in the US as Kenneth Bae - to hard labour. Mr Bae, believed to be a tour operator of Korean descent, is accused by Pyongyang of "anti-government crimes".