North Korean leader Kim Jong Un said in his New Year’s address that his country was in the "final stages" of launching an intercontinental ballistic missile (ICBM). US President-elect Donald Trump, whose inauguration was set for January 20, said on Twitter: "North Korea just stated that it is in the final stages of developing a nuclear weapon capable of reaching parts of the US. It won't happen!"

North Korea tested its first ICBM — the Hwasong-14 — on US Independence Day. Kim reportedly told his scientists that "the US would be displeased" by the launch. This, he said, was because "it was given a 'package of gifts' ... on its 'Independence Day.'" Trump wrote on Twitter in response: "North Korea has just launched another missile. Does this guy have anything better to do with his life?"

Pyongyang tested its second Hwasong-14 weeks later. Experts estimated the new rocket could reach the US mainland. Trump lashed out at North Korean ally China, writing in a Tweet: "I am very disappointed in China. Our foolish past leaders have allowed them to make hundreds of billions of dollars a year in trade, yet they do NOTHING for us with North Korea, just talk."

Trump appeared to threaten swift military action against Pyongyang when he told reporters: "North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen." North Korea responded by threatening to fire a medium-range ballistic missile into the waters around Guam, a US territory in the Pacific Ocean. It did not follow through.

Pyongyang sparked international outcry when it test-launched a mid-range ballistic missile — the Hwasong-12 — over Japan. The UN Security Council unanimously condemned the test. Trump said in a White House statement: "Threatening and destabilizing actions only increase the North Korean regime’s isolation in the region and among all nations of the world. All options are on the table."

North Korea announced it had successfully tested its sixth nuclear weapon. Pyongyang said it was a powerful type of nuclear weapon called a hydrogen bomb and that it could be placed on top of a ballistic missile. Trump wrote on Twitter: "The United States is considering, in addition to other options, stopping all trade with any country doing business with North Korea."

In his first speech at the United Nations, Trump called North Korea a "rogue state" and said Washington "will have no choice than to totally destroy North Korea" if Pyongyang failed to stop its nuclear weapons program. Referring to Kim, he added: "Rocket man is on a suicide mission for himself and his regime." Kim called Trump a "mentally-deranged US dotard" two days later.

North Korea test-fired its third ICBM of 2017. Pyongyang claimed it was a new missile, the Hwasong-15, which was superior to the Hwasong-14 and could hit any target on the US mainland. The US urged allies, including Germany, to break diplomatic ties with North Korea. Berlin ignored the call. Trump also called Kim a "sick puppy."

Kim said in his 2018 New Year's address that the North had completed its nuclear weapons program and that a "nuclear button" was on his desk at all times. Trump wrote two days later on Twitter: "Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!"

South Korean President Moon Jae-in welcomed Kim's sister, Kim Yo Jong, at the presidential house in the South Korean capital. She handed a letter to Moon inviting him to meet the North Korean leader in Pyongyang. Tensions appeared to be thawing. Seoul and Pyongyang had already agreed to send a unified hockey team to compete at the Winter Olympics in Pyeongchang, South Korea.

South Korean National Security Adviser Chung Eui-yong led a delegation on March 5 to Pyongyang to discuss the potential for peace talks. The next day, Chung said both sides had agreed to hold a joint summit in April and set up a telephone hotline between the two capitals. He also said Pyongyang would agree to stop its nuclear weapons and missile tests if the US agreed to hold talks with the North.

Chung flew on to Washington, D.C. to speak with Trump. After the meeting, Chung told reporters the US president had agreed to meet Kim by May. Trump later wrote on Twitter: "no missile testing by North Korea during this period of time. Great progress being made but sanctions will remain until an agreement is reached. Meeting being planned!" Foreign leaders welcomed the historic breakthrough.

A week before the scheduled meeting at the border between South Korean President Moon Jae-in and North Korean leader Kim Jong Un, Moon said North Korea wanted "an end to the hostile relations" and had expressed a commitment to "complete denuclearization" of the peninsula. The next day, the telephone hotline was connected for the first time since February 2016, so Moon and Kim could talk directly.

Kim announced North Korea would stop nuclear and missile tests. Kim said: "We no longer need any nuclear test or test launches of intermediate and intercontinental range ballistic missiles, and because of this the northern nuclear test site has finished its mission." However, no mention was made of its stored nuclear materials and equipment.

Kim and Moon Jae-in meet in the border town of Panmunjom in the Demilitarized Zone (DMZ) that has divided the two Koreas since the Korean War in 1953. The two leaders vowed to work towards a nuclear-free Korea and pledged an end to war. It was the first time a North Korean leader had set foot across the border since the 1950s and paves the diplomatic way for a Trump-Kim meeting in May or June.

South Korea announces its propaganda loudspeakers are to be switched off for good. They had been silenced temporarily ahead of the inter-Korean summit, which prompted the North to halt its broadcasts, too. Pyongyang also said it would adjust its time zone to that of the South as a symbolic gesture. North Korea has been half an hour behind the South since 2015.

After North Korea slammed US Vice President Mike Pence for comparing North Korea and Libya, Donald Trump abruptly canceled the summit. Trump said the move was due to "tremendous anger and open hostility" displayed by Pyongyang.

A day after scrapping the summit, Trump suggested he was still open to meeting Kim. US and North Korean officials met during the following week and on June 1, Trump met one of Kim's closest aides, Kim Yong Chol, in the White House. Shortly thereafter, Trump said the summit would indeed take place on June 12 in Singapore. "I think you're going to have a very positive result in the end," he said.

Trump and Kim met in Singapore as planned. They smiled, shook hands and praised how far they had come in overcoming their previous animosity. The summit ended with both leaders signing a short joint declaration that committed Pyongyang to denuclearize and the US to providing unspecified "security guarantees" to the North. Trump also said he would invite Kim to the White House.

In an effort to promote unity after taking power in China in 1949, the Communist Party abolished all the country's time zones to make just one — Beijing Time (GMT/UTC+ 8 hours). It means that people in the far west of the country, such as the Xinjiang province, must get up earlier than their body clocks might want. Some set their clocks back two hours, something at times viewed as disloyal.

Spain's late-night lifestyle may have more to do with a historic decision than with Latin temperament. Dictator Francisco Franco stayed neutral (at least on paper) during World War II. But in a show of solidarity with Hitler in 1940, he switched from GMT to Central European Time — in line with Nazi Germany. That's why the sun rises and sets much later in Spain, and life is a little later, too.

North Korea changed its timekeeping in 2015, at a time of high tension in the region. The reason given though, was more historic. Pyongyang wanted to extinguish a vestige of Japanese colonialism. Both Koreas had been using the same time zone as when Japan ruled the Korean Peninsula from 1910 to 1945.

Nepal is also a little strange in its measure of time, choosing to be 15 minutes ahead of neighboring India and five hours, 45 minutes ahead of GMT. The idea was to distinguish the relatively small Himalayan country from India, and generate a feeling of national pride in being different.

In 2016, Venezuelan President Nicolas Maduro called for all clocks to be move forward by 30 minutes — four hours behind GMT. The move reversed a time-change introduced by predecessor Hugo Chavez in 2007. The idea was that an extra bit of daylight would reduce the amount of electricity needed. It was even given a positive spin with the tag "half an hour more future."

The biggest single leap in time change must go to the Pacific country of Samoa, which jumped a full day across the International Dateline in 2011. The island nation went from 21 hours behind Sydney Time to three hours ahead. The decision aimed to break with the legacy of a 19th century king, who had wanted his islands more aligned with America, and improve ties with Australia and New Zealand.