John Bolton, Trump's national security adviser, said Tuesday the president wants to hold a second meeting with Kim because North Korea has not lived up to the commitments it made last summer.
While the base at Yeongjeo-dong has always been known to United States intelligence agencies and analysts, researchers at the Middlebury Institute of International Studies at Monterey told CNN that the images reveal construction on a new facility just seven miles away from the older site that had not been previously publicly identified.
"Satellite images show that the base remains active", an institute report states, CNN reported.
- Researchers at a college in Monterey said they have proof North Korea is not only operating and expanding a known missile base, but there's another unknown site that is also active and growing.
As of August 2018, researchers said North Korea is continuing to construct an extremely large underground facility.
Experts told the United States news network that the site's location made it suitable to host North Korea's newest long-range missiles, including ones that could carry nuclear warheads.
"We watch North Korea very closely", Pentagon spokesperson Lt. Col. Chris Logan told CNN.
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Dr Carrascosa said that the test had been trialled on 200 tissue samples, detecting cancer with up to 90 per cent accuracy. Sign up today to get biotech news and updates delivered to your inbox and read on the go.
"Absent mechanisms for the on-the-ground verification by inspectors, we can not confirm that North Korea has taken any other denuclearization steps at this time", he said.
U.S. president Donald Trump said after the summit that Chinese president Xi Jinping had agreed to work with him on North Korea, amplifying Pyongyang's concerns over the summit's implications for China's North Korea policy, including Chinese support for an easing of United Nations sanctions.
The two men met in Singapore in June and signed a vaguely worded document that pledged to "work toward" the complete denuclearization of the Korean peninsula, though it did not detail specifics on how this would come about.
Last month, images revealed that North Korea had been working to improve 16 hidden ballistic missile bases, despite halting moves on dismantling a major site in order to appease the US.
Kim announced the dismantlement of a nuclear facility at another site in Nyongbyon at a summit with South Korean leader Moon Jae-in in September. A headquarters area is positioned at the mouth of the valley, the images show.
The bases are believed to serve as shelters for mobile missile launchers, and would be able to store the country's newest long-range missiles, including those capable of carrying nuclear warheads.