North Korea began the "rapid rebuilding" of the long-range rocket site at Sohae Launch Facility about 48 hours after last week's Hanoi summit collapsed, according to commercial imagery and analysis from the researchers at Beyond Parallel. They say these launches use technology similar to the kind used for intercontinental ballistic missiles.

"This renewed activity, taken just two days after the inconclusive Hanoi Summit between President Donald Trump and North Korean leader Kim Jong Un, may indicate North Korean plans to demonstrate resolve in the face of U.S. rejection of North Korea's demands at the summit to lift five U.N. Security Council sanctions enacted in 2016-2017," the analysts said.

According to Victor Cha, one of the authors of the report, the activity at the launching station indicates that North Korea will conduct another missile test soon:

"The activity they are undertaking now is consistent with preparations for a test, though the imagery thus far does not show a missile being moved to the launch pad. The activity on the ground shows us that they do have a (nuclear intercontinental ballistic missile) capability that is not just developmental, but in the prototype phase. They've already tested a few of these and it looks like they're preparing the launch pad for another act."

Commercial satellite imagery shows the progress at the launching facility.

The White House, via Press Secretary Sarah Huckabee Sanders, declined to comment on the report.

"We don't comment on intelligence," Sanders said. “We are continuing to have conversations, as the president has said, we'll see what happens… Beyond that, I am not going to comment.“

The latest information about North Korea's activities opened up the Trump administration to criticism, with many saying that President Donald Trump had been fooled by a dangerous autocrat.

The Hanoi summit collapsed when North Korea demanded that the U.S.-led sanctions be lifted.

"Basically, they wanted the sanctions lifted in their entirety, but we couldn't do that ... we had to walk away from it," Trump said after the summit.

International sanctions have crippled the North Korean economy for years, and Kim, as expected, demanded that sanctions be lifted in exchange for dismantling the hermit kingdom's nuclear program. Trump cut the talks short once it became clear Kim would not commit to total denuclearization, a goal the two of them agreed upon during their Singapore summit in 2018.

It was a harsh blow for a president who'd earlier assured his detractors that talks were going swimmingly.

Earlier this week, the president claimed that he ended military drills with South Korea "to save hundreds of millions of dollars for the U.S. for which we are not reimbursed." He insisted that "reducing tensions with North Korea at this time is a good thing."

Trump has criticized U.S. intelligence agencies on North Korea's ballistic missile program since the start of his term. There is no word on when Trump and Kim will meet again.