U.S. government officials have accused North Korea of increasing its nuclear capabilities at several secret sites over the last few months.

North Korea May Be Raising Nuclear Production

Officials are also saying the authoritarian regime’s leader Kim Jong-Un may be attempting to hide these sites while hoping to earn more concessions through nuclear negotiations with President Donald Trump‘s administration.

Trump voiced great confidence after his June 12 historic summit with Kim in Singapore, and said on Twitter he believed North Korea “was no longer a nuclear threat.” However, the meeting was heavily criticized for its lack of major details, and for the fact that not much was accomplished because Trump seemed to have made major concessions while receiving very little in return. Trump has drawn great controversy for praising Kim despite the harsh punishments he has dealt to his people as a dictator.

Recent intelligence reports have alleged North Korea has been raising its production of uranium for nuclear weapons over the last few months.

“There is absolutely unequivocal evidence that they are trying to deceive the U.S.,” one official said, citing the reports.

Earlier this year, it was reported that North Korea had destroyed its only known nuclear test site.

“The observed activity appears inconsistent with a North Korean intent to abandon its nuclear weapons programs,” Bruce Klingner, a former CIA analyst and North Korea expert at the Heritage Foundation, told NBC News. “There seems little reason to continue expansion plans if the regime intended to dismantle them as would be required under a denuclearization agreement.”

In an interview with Fox News on Sunday, Trump confessed he believed Kim might not respect the denuclearization agreement they reached last month.

“Have I been in deals, have you been in things where, people didn’t work out? It’s possible,” said Trump.

On Saturday, the Washington Post said U.S. intelligence agencies believe North Korea is plotting to hide the number of nuclear warheads in its arsenal.

This past weekend, a U.S. envoy met with North Korean officials at the demilitarized zone.