WASHINGTON -- North Korea has continued to take down a missile engine testing site in line with an agreement reached by its leader Kim Jong-un and US President Donald Trump, a US website monitoring the regime said Tuesday.

New satellite imagery from Friday indicates that work continues at the vertical engine test stand as well as the launch pad at the Sohae Satellite Launching Station, according to 38 North, a project of the Stimson Center think tank.

The development comes about two weeks after 38 North reported the beginning of dismantlement activities at the site.

"At the vertical engine test stand, used for testing and development of engines for ballistic missiles and space launch vehicles, the North Koreans have continued to tear down the steel base structure and appear to be removing fuel and oxidizer tanks from dismantled bunkers," the article said.

It said that parts of the launch pad have also been removed, but it is unclear whether the activity is related to dismantlement or the start of some modification on the structure.

"These activities, however, must be viewed cautiously as 'first steps' since neither are presently permanent or irreversible," according to 38 North. "The demolition of the test stand's concrete foundations, launch pad's gantry tower, pad foundation and exhaust deflector, etc., would represent more permanent and irreversible actions as there is no known facility with equivalent capabilities elsewhere in the country."

Dismantling the missile test site was a promise Kim made verbally at his June meeting with Trump in Singapore, according to the US president. In a joint statement, Kim also committed to work toward the "complete denuclearization" of the Korean Peninsula in exchange for security guarantees from the US

Trump lauded the reported dismantling shortly after 38 North came out with its first analysis.

"New images just today show that North Korea has begun the process of dismantling a key missile site and we appreciate that," he said.

But US Secretary of State Mike Pompeo struck a more cautious tone.

"We've been pressing for there to be inspectors on the ground when that engine test facility is dismantled, consistent with Chairman Kim's commitment," he said. (Yonhap)