Trump told reporters after their June 12 summit that Kim had pledged to dismantle one of his missile installations, which would be North Korea's most concrete concession at the landmark meeting in Singapore. But the president at the time did not name the site.
A U.S. official on Wednesday identified it as the Sohae Satellite Launching Ground, saying North Korea "has used this site to test liquid-propellant engines for its long-range ballistic missiles." Pyongyang has said its missiles can reach the United States.
"Chairman Kim promised that North Korea would destroy a missile engine test stand soon," the official told Reuters, speaking on condition of anonymity. There was no immediate word on the exact timetable, and North Korea has not publicly confirmed that Kim made such a commitment.
CBS News was the first to identify the site, which is the newest of North Korea's known major missile testing facilities.
The U.S.-based North Korea monitoring group 38 North said in an analysis at the end of last week that there had been no sign of any activity towards dismantling Sohae or any other missile test site.
"The United States will continue to monitor this site closely as we move forward in our negotiations," the U.S. official said.
It was reported to have been established in 2008 and has research facilities nearby for missile development as well as a tower that can support ballistic missiles. The site is mainly used to test large Paektusan engines built for long-range missiles such as the Hwasong-15.
Ahead of the summit, North Korea announced the suspension of its testing of intercontinental ballistic missiles and also closed its nuclear bomb test site. U.S. officials, however, have cautioned that such actions are reversible.
Asked on Wednesday whether North Korea has done anything towards denuclearisation since the summit, U.S. Defense Secretary Jim Mattis told reporters: "No, I'm not aware of that. I mean, obviously, it's the very front end of a process. The detailed negotiations have not begun. I wouldn't expect that at this point."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)