Photo/IllutrationNorth Korean leader Kim Jong Un watches the Nov. 29 launch of the Hwasong-15 intercontinental ballistic missile. This photo was distributed by the Korean Central News Agency. (Korea News Service)

SEOUL--North Korean leader Kim Jong Un has ordered the preparation of an even larger ballistic missile capable of successfully re-entering the Earth's atmosphere, possibly for launch in September.

A defector knowledgeable about North Korea's missile development program said Kim Jong Un gave the directive at a meeting in Pyongyang on Dec. 11 and 12 involving high-ranking officials involved in the munitions and science sectors. They had gathered for a convention on the military industry.

The plan appears to be preparing the missile for launch on Sept. 9, 2018, which marks the 70th anniversary of the founding of North Korea by Kim Il Sung, the grandfather of the current leader.

The new missile would be an even larger version of the Unha-3, which had a total length of 30 meters and was launched in December 2012 and February 2016. The Unha-3, an improved version of the Taepodong-2, is a three-stage, long-range ballistic missile.

The defector said the new missile would be considered the "Unha-4." The Unha-3 was launched from the long-range ballistic missile launching site in Tongchang-ri, North Phyongan province.

Development of the missile body is all but complete, but it is expected to take about six months to prepare for a launch.

According to intelligence sources, there was no confirmation as of Dec. 30 of any specific signs North Korea was preparing for a ballistic missile launch, including at the Tongchang-ri site.

North Korea has said it was planning to launch a new rocket to carry a satellite into space.

The defector said there were likely two major objectives in launching a new long-range missile. One would be the use of a satellite for guidance and observation of future missile launches. The other could be to use the pro forma launch of a satellite into space to test whether the missile was capable of re-entry into the atmosphere.

In its Dec. 25 digital version, the Rodong Sinmun, the mouthpiece of the Workers' Party of Korea, said, "North Korea will continue to push forward with the development of a peaceful space program."

It added, "No one can interfere with or criticize such a peaceful space program."

North Korea launched the Hwasong-15 intercontinental ballistic missile with a range of more than 13,000 kilometers on Nov. 29, but U.S. officials apparently believe that missile broke up as it tried to re-enter the atmosphere.