A pre-emptive, surgical strike against Kim Jong Un is risky, but his regime will soon have a nuclear-tipped intercontinental ballistic missile, say Isabel Reynolds and Enda Curran.

China is worried about a US missile defence system deployed in South Korea to head off an attack by the North. What is at stake, asks David Tweed.

North Korea has made more threats against its enemies, vowing to take unspecified "powerful" measures over a US plan to deploy an advanced missile defence system in South Korea.