Unnamed U.S. officials tell the Post that spy satellites have detected activity at a factory outside Pyongyang that produced long-range missiles as recently as July 7.
Reuters quotes an official as saying it is unclear how far the work has gone.
During the meeting, Maharani invited a joint North and South Korean team to take part in the Asian Games, as part of efforts to improve relations between the countries and strengthen reconciliation progress on the Korean Peninsula.
After the first meeting between sitting leaders from the two countries, the two men pledged to work towards denuclearisation.
North Korea has threatened to attack the US and its allies with nuclear weapons on numerous occasions.
Besides being the US's largest trading partner, China is arguably the most important player in Trump's "maximum pressure" campaign to force Kim to give up his nuclear arsenal.
Pompeo assured lawmakers that the USA was working toward finding a solution without easing its sanctions against North Korea, but also admitted during his testimony that it was "continuing to create fissile material".
That was the latest in a series of reports casting doubt on whether the communist state is truly committed to abandoning its hard-won nuclear weapons.
However, a USA official told news agency Reuters that a liquid-fuelled ICBM didn't "pose almost the threat that a solid-fuelled one would because they take so long to fuel".
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The government is now preparing to deport as many as 1,000 of the parents who have a final deportation order lodged against them. John Cornyn, R-Texas, said the agencies should be blamed when Congress has offered "no plausible or workable solution at all".
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Tim Cook spent an unusual amount of time focused on Apple's services division during the Q3 earnings call, and for good reason. Apple , meanwhile, has focused more on services such as the App Store and its entertainment businesses as growth drivers.
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In a statement to The New Yorker , Moonves acknowledged that he "may have made some women uncomfortable by making advances". Meanwhile, CFRA Research downgraded CBS on Monday from buy to hold, citing the unclear near-term outlook for the company.
Photos and infrared imaging indicate vehicles moving in and out of the facility at Sanumdong, the official told Reuters on condition of anonymity because the intelligence is classified. But many experts say those are neither irrevocable nor serious steps that could show the country is honest about denuclearization.
"[The facility] is not dead, by any stretch of the imagination", said Mr Lewis.
Intelligence officials told the Post that trucks and shipping containers can be seen at the facility.
North Korea halted nuclear and missile tests, shut down its nuclear testing site and began dismantling facilities at its rocket launch site.
This indicated that there had not been a complete stop in activity during the summit talks.
The North demonstrated sharp progress in its program past year when it test-fired numerous missiles and conducted its sixth and most powerful nuclear test.
North Korean leader Kim Jong Un agreed during his meeting with Trump to "work toward" the "denuclearization" of the Korean Peninsula. North Korea has steadfastly argued its nuclear weapons are meant to neutralize alleged USA plans to attack it.
The White House said it did not comment on intelligence, Reuters reported, while a senior official at South Korea's presidential office said US and South Korean intelligence agencies are closely looking into various North Korean movements. The new US military intelligence assessment was first reported on Monday by the Washington Post.
Secretary of State Michael Pompeo, who's leading nuclear negotiations with North Korea, acknowledged in Senate testimony last week that North Korean factories "continue to produce fissile material" used in making nuclear weapons.