US Defence Secretary Chuck Hagel said plans to bolster the country's missile defences were in response to "irresponsible and reckless provocations" by North Korea, which threatened a preventative nuclear strike against the US last week.
In addition to the 14 new anti-missile interceptors being added at Fort Greely in Alaska, the Pentagon has also left open the possibility of creating a site on the US East Coast where it could field more interceptors capable of striking down an incoming missile.
Hagel told a news conference, "By taking the steps I outlined today we will strengthen our homeland defence, maintain our commitments to our allies and partners, and make clear to the world that the United States stands firm against aggression".
Last week, North Korea issued a threat to stage a pre-emptive nuclear attack against the US as the United Nations readied new sanctions against Pyongyang in response to its nuclear test on February 12.
More top news
Mr Justice Hayden told the High Court that the case of the terminally-ill boy has now reached its ‘final chapter’.
Board of Deputies and Jewish Leadership Council say their meeting with the Labour leader was a ‘disappointing missed opportunity’.
The U.S. president deemed Iran deal 'insane' while speaking with French President Emmanuel Macron in the Oval Office.