North Korea has moved its missiles away from a coastal launch pad after weeks of speculation the country was planning another missile or nuclear test, a senior U.S. defense official confirms to Fox News.

Pentagon officials say the two Musudan missiles have been taken from the launch site and are being returned to garrison.

However, special assistant to the president and senior director for Asian affairs Daniel Russel cautioned Monday that despite the news, it would be premature to make a judgment on whether this North Korean provocation cycle is going up, down or zigzagging.

"Many analysts have anticipated North Korea's provocation cycle would culminate in some grand fireworks display and no one can rule that out," he told Fox News.

The prospect of a North Korea missile or nuclear test following weeks of harsh rhetoric from Pyongyang concerned South Korea, the U.S. and others. 

Secretary of State Kerry warned North Korea last month not to conduct a missile test, saying it would be an act of provocation that "will raise people's temperatures" and further isolate the country and its people. 

A White House official tells Fox News they are continuing to monitor the situation.

The medium-range Musudan missile has a range of 2,180 miles capable of flying over Japan, Foreign Minister Yun Byung-se told lawmakers in Seoul in March. 

If the Musudan missile is launched, it would be the first mobile test of this weapon.

Fox News' Jennifer Griffin and The Associated Press contributed to this report.