Timeline of U.S.–North Korea diplomatic history

North Korea ratifies the Nuclear Non-Proliferation Treaty in December. Under this multilateral agreement, countries commit to halt the spread of nuclear weapons and technology and promote peaceful cooperation on nuclear energy.

North Korea and South Korea agree to denuclearize the Korean Peninsula. The treaty bans nuclear weapons and commits both countries to use nuclear energy only for peaceful purposes.

North Korea rejects inspections by the International Atomic Energy Agency and announces its intent to leave the Nuclear Non-Proliferation Treaty.

It later suspends its withdrawal from the treaty after talks with U.S. diplomats in New York. The first inspections in North Korea end up taking place in March 1994.

Jimmy Carter travels to North Korea in June and meets with Kim Il Sung, the country’s founder and leader. Carter is the first former U.S. president to visit North Korea. His trip lays the groundwork for a U.S.-North Korea agreement.

In October, the United States and North Korea sign the “Agreed Framework.” North Korea agrees to freeze construction of nuclear reactors and production of plutonium in exchange for aid, fuel shipments and other benefits.

The United States and North Korea alternate as hosts for goodwill trips. In October, North Korean senior military official Jo Myong Rok visits President Bill Clinton in Washington.

Later that month, Secretary of State Madeleine Albright flies to Pyongyang and meets with North Korea’s leader, Kim Jong Il, to try to expand the Agreed Framework and prepare a potential visit by Clinton. The two sides do not reach agreement on a visit or new deals.

Several rounds of the Six-Party Talks, involving the United States, North Korea, South Korea, Japan, China, and Russia, take place after North Korea’s withdrawal from the Nuclear Nonproliferation Treaty in 2003.

Little progress occurs until February 2007, when North Korea agrees to shut down its nuclear facilities in exchange for fuel aid and measures aimed at normalizing its relations with the U.S. and Japan.

The Six-Party Talks end after North Korea holds an announced missile launch, a move condemned unanimously by the United Nations Security Council.

In response to the U.N.’s condemnation, North Korea pulls out of the Six-Party Talks and says it will not be bound by any agreement reached at the talks. North Korea expels nuclear inspectors and informs International Atomic Energy Agency officials that it will resume its nuclear weapons program.

Since exiting the Six-Party Talks, North Korea has at times said it will take steps toward denuclearization. But it continues to conduct tests in violation of international law, including three nuclear tests and over 40 ballistic-missile launches from 2016 to 2017.