North Korea has moved two missiles from launch sites on the country's eastern coast, U.S. officials said Monday, signaling lowered tensions following worries Pyongyang was ready to test-fire the weapons.

The Musudan missiles had been ready to launch at any moment, but "they moved them," a U.S. defense official, who spoke on condition of anonymity, told AFP.

North Korea's move meant there was no longer an imminent threat of a launch, and Pyongyang would have to make preparations before returning to a launch-ready status, two U.S. officials said.

Amid dire threats and bellicose language from North Korea, two Musudan missiles had been deployed to the east coast, and the United States and its allies Japan and South Korea had braced for a possible test-launch in the run-up to national celebrations on April 15.

Japan and South Korea stepped up its missile defenses, while the U.S. military deployed two destroyers equipped with anti-missile weapons and a powerful radar to the area to thwart any possible launch.

Commanders told lawmakers U.S. forces would be ready to shoot down any missile that threatened allies or U.S. facilities in Guam.

But North Korea never launched a missile and eventually toned down its inflammatory rhetoric, with the crisis appearing to ease in recent days.

Pentagon spokesman George Little noted the change in North Korea's words, telling reporters Monday the "provocation pause" was a positive development.

A Musudan missile has an estimated range of about 640 kilometers to 5,630 kilometers, according to military officers.

Analysts have disagreed about the missile's capabilities and believe Pyongyang has never tested the weapon in flight.

North Korea has several hundred short and medium-range missiles available that could reach targets in Japan or South Korea, according to the Pentagon. (AFP)