A nuclear explosion at the Nevada Test Site in 1953. (Photo courtesy the National Nuclear Security Administration)

North Korea likely can develop a miniaturized nuclear weapon that can be launched from a mobile launcher, the top U.S. general in South Korea said — a capability that weapons experts have previously said they doubt is within the reach of the government of Kim Jong-un.

Army Gen. Curtis Scaparrotti, commander of U.S. Forces Korea, told reporters at the Pentagon on Friday that North Korea has claimed to have already done so, and has had the right connections and technology to make it happen.

“I think given their technological capabilities, the time that they been working on this, that they probably have the capabilities to put this together,” he said. “I don’t believe that they have. I don’t know that they have at this point.”

Any “mini-nuke” would likely be launched from a system mounted on a truck, and carried by an intermediate or long-range missile. U.S. officials have mixed opinions on how far North Korea has come in developing one, but most believe that any missile launched will have very low reliability.

Rear Adm. John Kirby, the Pentagon press secretary, said Friday afternoon that Scaparrotti speaks with Defense Secretary Hagel about the issue, and the Defense Department is monitoring the situation.”

But they have not moved — we have not seen evidence that they’ve done it,” Kirby said. “And we’ve not seen certainly any evidence that they’re testing or in development of it.”

President Obama said in April that there is no “magic bullet” to influence officials in Pyongyang, North Korea’s capital. 

Obama and South Korean President Park Geun-hye signaled in April that they were considering delaying a plan to give Seoul control of its own troops during any future war on the Korean Peninsula, rather than placing them under U.S. command. Defense Secretary Chuck Hagel and South Korean Defense Minister Han Min Koo formalized that Thursday. Instead of turning operational control of troops over to South Korea as planned in December 2005, they signed a memorandum of understanding that effectively postpones it indefinitely.

This post was updated with additional reporting.