The United States military conducted a successful missile defence test after it fired an ICBM-type missile from the Kwajalein Atoll in the Marshall Islands and then fired a missile to intercept it from Vandenberg Air Force Base in California.

The Missile Defence Agency said it was the first live-fire test against a simulated ICBM for the Ground-based Midcourse Defence (GMD) and hailed it as an "incredible accomplishment."

A successful test was by no means guaranteed and the Pentagon sought to manage expectations earlier in the day, noting that the United States had multiple ways to try to shoot down a missile from North Korea.

Prior to the launch, the GMD system had successfully hit its target in only nine of 17 tests since 1999. The last test was in 2014.

North Korea has dramatically ramped up the pace of its missile tests over the past year, with a goal of developing an ICBM that can strike the US mainland.

The continental United States is around 9,000 km (5,500 miles) from North Korea. ICBMs have a minimum range of about 5,500 km (3,400 miles), but some are designed to travel 10,000 km (6,200 miles) or farther.