A former national security official said Wednesday on “Rising” that North Korea is unlikely to give a full accounting of its missile sites ahead of the upcoming summit in Vietnam later this month between President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE and North Korea leader Kim Jung-un.

"There has been a lot of press recently that there has been new missile sites discovered that North Koreans hadn’t declared," Fred Fleitz, who briefly served on President Trump’s National Security Council, told Hill.TV's Krystal Ball and Buck Sexton.

"But that’s actually a little bit deceptive because North Korea has not been required to submit a declaration yet — they're supposed to."

"We want them to submit it, we also know that when they submit it, it's probably going to be incomplete and we're going to have to go back and say 'we know you have this,' " Fleitz said.

In a report that was released by the Center for Strategic and International Studies (CSIS) in January, researchers reported that there were at least 20 undisclosed North Korea missile sites.

Fleitz said he would would consider the second summit a "big win" if the U.S. could get inspectors at one of the nuclear test sites where North Korea detonated at least five nuclear devices.

Trump and Kim are scheduled to meet in Hanoi, Vietnam on Feb. 27 and 28.

This marks their second summit, after their historic meeting in Singapore last year. In November, Trump became the first sitting U.S. president to meet with the long-time North Korean leader face-to-face.

At the summit in Singapore, the two leaders signed a joint agreement, where North Korea pledged “to work toward the complete denuclearization of the Korean peninsula.” At the time, the statement was widely criticized for lacking any concrete details on how to achieve denuclearization.

The commander of U.S. troops on the Korean Peninsula praised the second summit between Trump and Kim on Tuesday. However, he also warned that there’s been “little to no verifiable change” in Pyongyang’s nuclear capabilities and said that the country still remains a military threat.

Fleitz remains optimistic about the second summit, saying the goal is to keep moving denuclearization talks forward.

"We all knew this was going to be difficult, that the North Koreans were going to drag their feet, but I think there's hope that we're going to be getting somewhere at the summit," he said.

—Tess Bonn