Since inheriting power in late 2011, Kim Jong Un has dramatically increased the speed and scope of North Korea’s development of nuclear weapons and the ballistic missile to carry them.

In 2016 his regime drew international condemnation by testing two nuclear devices and more than 20 ballistic missiles. The sabre-rattling has continued in 2017, with Pyongyang increasing the pace of ballistic missile tests and unveiling new, advanced rockets.

For the international community, particularly the US, there is growing concern that Mr Kim will soon master the technology to equip an intercontinental ballistic missile with a nuclear warhead - a development that could imperil large swaths of the US mainland. North Korea has already tested one rocket theoretically capable of reaching North America, and other ICBMs are in development.