North Korea is said to have been producing 12 new nuclear weapons since the first summit between President Trump and Kim Jong Un in Singapore last June According to the Wall Street Journal, activity at the atomic bomb sites in the north has increased since the historic meeting.
Analysts believe that North Korea currently has only 20 and 60 nuclear bombs.
The images appear to show both trucks and people transporting materials to and from the sites, including the Yongbyon Nuclear Research Center. Kim has previously expressed his willingness to close the facility under a future contract.
The photos suggest that the North, despite hopeful rhetoric from both sides, still has no intention of giving up its nuclear arsenal.
One second The meeting between Trump and Kim in February failed after the US had ended the negotiations abruptly.
"We had a really productive time. We had some options. At that point, we decided not to choose any of the options, "Trump said at a press conference decision. "Sometimes you have to go."