North Korea has not taken additional steps to dismantle its main missile test site since early August, a U.S. website monitoring the regime said Thursday.

38 North, a project of the Stimson Center think tank, said commercial satellite imagery from Sept. 27 showed no further dismantlement of the Sohae Satellite Launching Station since Aug. 3.

North Korean leader Kim Jong-un pledged at his Sept. 19 summit with South Korean President Moon Jae-in to permanently shut down the site in front of international inspectors.

"The lack of activity could be for a number of reasons," 38 North said in an article posted on its website. "For example, North Korea may be waiting to arrange a visit of international observers or for the results of (U.S.) Secretary of State Mike Pompeo's upcoming visit."

It should not be interpreted as Pyongyang's failure to follow through on its pledge, the website said.

Pompeo is due to meet with Kim in Pyongyang on Sunday to discuss efforts to denuclearize the regime and set up a second summit between Kim and U.S. President Donald Trump.

At the first summit in Singapore in June, Kim committed to work toward "complete" denuclearization of the Korean Peninsula in exchange for security guarantees from the United States.

38 North said the vertical engine test stand and the launch pad at the facility have remained in the same condition since Aug. 3.

The most important and most easily verified dismantlement activity at the engine test stand would be to destroy its foundation, which would be difficult to rebuild and easily observable by satellite, according to the website.

It also said dismantlement of the gantry tower for satellite launch vehicles would be an important step.

"While many experts have dismissed this step as unimportant, it would effectively signal that Pyongyang is discontinuing what has been an active space (satellite) program for over a decade -- a program that has probably cost tens if not hundreds of millions of dollars to develop," 38 North said.

"In doing so, the North will also close a potential loophole in future ballistic missile limitation agreements, as the Sohae launch pad could be used to launch a space launch vehicle derivative of Pyongyang's Hwasong-15 intercontinental ballistic missile (ICBM), allowing them to at least claim the test was for legitimate peaceful purposes, an argument that would resonate with China and Russia."

Source: Yonhap News Agency