North Korea has also been testing the Hwasong-14 ballistic missile. This has a range of 8,000km - although some studies have suggested it could travel as far as 10,000km, making it capable of reaching New York. It is the first of North Korea's intercontinental ballistic missiles The Hwasong-15 missile is believed to have a range of 13,000km, putting all of the continental US in its sights. In October 2020, North Korea unveiled the latest of its ballistic missiles - the Hwasong-17 - believed to have a range of 15,000km or more. It could possibly carry three or four warheads, rather than only one - making it harder for a nation to defend itself. Several attempts to launch the longer-range Hwasong-17 are thought to have failed, although it may have been used in a test carried out on 24 March this year. The unveiling of the new missiles appeared to be a message to the Biden administration of the North's growing military prowess, say experts. "North Korea has been testing missiles with longer and longer ranges," says Joseph Byrne, research fellow at the Royal United Services Institute. "It could be the precursor to it testing another nuclear warhead, which has been predicted for some time," he adds. In March 2021, it carried out a launch of what it called a "new-type tactical guided projectile", which it said was able to carry a payload of 2.5 tons - so capable in theory of carrying a nuclear warhead. Analysts at the James Martin Center for Nonproliferation Studies told Reuters that it appeared to be "an improved variant" of a previously tested missile, the KN-23.