The BBC reported on Monday that South Korea is worried that the North is planning more missile launches.
Take a look at the nine countries that (supposedly) have nuclear weapons.
1. United States
The US was the first country to develop nuclear weapons, successfully testing the world’s first during World War Two, and ending the war in the east by dropping two bombs on Japan under the orders of President Harry S. Truman. The bombs ended the war, but contributed to an arms race during the subsequent Cold War. According to the International Campaign to Abolish Nuclear Weapons (ICAN), the US has 6,800 nuclear weapons.
The USSR began testing nuclear bombs following the Second World War. When the Soviet Union broke up at the end of the Cold War, Russia inherited most of its nuclear weapons, and has a reported 7,000 warheads to this day, as reported by ICAN.
ICAN also reports that together, the US and Russia have 1,800 nuclear missiles ready to launch immediately should the situation require it.
3. United Kingdom
The fifth and final member of the so-called nuclear club – countries who have used nuclear weapons before the Non-Proliferation Treaty– is China. The Communist-led state has a reported 270 warheads.
According to the Nuclear Weapons Archive, India conducted its first nuclear test in 1974, and has a reported 110 – 120 nuclear weapons.
The partition of British India into India and Pakistan seventy years ago has played a role in the tensions between the two countries. Following the war between the two nations of 1971, Pakistan started to develop nuclear weapons, and has an estimated 120-130 nuclear weapons in its arsenal, according to ICANW.
According to the Guardian, Israel has been making nuclear weapons since the 1950s, making it the only country in the Middle East to have such weapons. After years of secrecy, the paper reports that the Knesset’s Speaker admitted that the country had a stockpile of nuclear weapons, a total which is estimated to stand at around 80.
9. North Korea
According to the BBC, North Korea admitted to carrying out its first nuclear tests in 2006 – all underground. Over the years the country has been improving its nuclear technology culminating in a “perfect success of a test this month", according to the BBC.
How legitimate are the countries new claims? What will North Korea's Kim Jong-un do next?