In a major escalation of rhetoric, North Korea issued a new threat of a nuclear strike on the United States on Thursday.

The U.S.'s "reckless nuclear threat will be smashed by the strong will of all the united service personnel and people and cutting-edge smaller, lighter and diversified nuclear strike means of the DPRK and that the merciless operation of its revolutionary armed forces in this regard has been finally examined and ratified," according to an English-language version of the North Korean state news agency KCNA, which quoted a spokesman for the general staff of the North Korean army.

Most observers say North Korea is still years away from having the technology to deliver a nuclear warhead on a missile, but it does have plenty of conventional military firepower, including medium-range ballistic missiles that can carry high explosives for hundreds of miles.