The satellite imageries were released days after the second US-North Korea summit in Vietnam ended without any agreement.
US National security advisor John Bolton says Donald Trump would be 'disappointed' by a North Korea test
John Bolton appeared notably cautious when asked on ABC's "This Week" about a report that satellite imagery appears to show preparations at a North Korean site for the possible launch of a missile.
Responding to a question, the official said the US seeking a fully verified denuclearisation of North Korea.
Kim met with Chinese President Xi Jinping four times in the past year, most recently in January.
Trump predicted a "very successful" summit as the pair prepared for dinner at the luxury Sofitel Legend Metropole hotel in Hanoi to follow up on their initial historic meeting in Singapore in June.
A military guard of honour in pristine white uniforms presented arms as Kim strolled down the red carpet waving and grinning, surrounded by a phalanx of aides and security personnel.
In a statement, Pompeo said that the nuclear talks between the two countries would lead to long-lasting peace and stability on the Korean Peninsula.
The current North Korea-US talks have been stuck in an impasse due to their differences in the scale of denuclearization, US sanctions, and whether to issue a war-ending declaration.
It is the first time US secretary Mike Pompeo has visited North Korea since a summit between Donald Trump and Kim Jong-un in Singapore.
Friday's response by North Korean Vice Foreign Minister was more conciliatory, specifically praising Trump's efforts for a meet, something which none of his predecessors have ever tried before.
The decision to close the Punggye-ri nuclear test site had generally been seen as a welcome gesture by Kim to set a positive tone ahead of the summit with Trump, which was recentcaly called off.
It was on March 8 that a delegation visiting from South Korea came to the White House to deliver a message from Kim Jong Un to Trump
Pompeo made the comments after attending a White House meeting between President Donald Trump and the visiting South Korean President Moon Jae-in.
North Korea threatened to cancel the summit between Kim Jong Un and US President Trump if Washington presses ahead with its key demand for Pyongyang to unilaterally give up its nuclear arsenal.
The remarks come ahead of an unprecedented summit between Kim and Trump in Singapore on June 12 where North Korea's nuclear and missile programmes are expected to dominate the agenda.