Trump cited lack of "sufficient progress" in diplomatic efforts to denuclearize the North.

Skepticism has since grown about Trump's approach toward the communist nation despite his talk of a good relationship with its leader Kim Jong-un.

The ambassador pointed out the North knows that there will be no easing of sanctions and economic cooperation without continued negotiations and improved ties with the United States.

"Accordingly, it will maintain dialogue and improve relations with the US anyhow," he stressed.

The North has kept mum publicly on the cancellation of Pompeo's visit, which apparently reflects its prudent stance, Cho added.

On a possible rift between the allies over Seoul's plan to open an inter-Korean liaison office in North Korea's border city of Kaesong, he said related news reports are "overblown."

Advancing denuclearization talks is a shared core task of the two sides, he said, adding Seoul and Washington are in close consultations on the North Korea issue.

The State Department's spokesperson Heather Nauert also said earlier the allies may have "minor disagreements," but the notion of a conflict is simply overblown.

The department has appointed its new point man on Pyongyang, Stephen Biegun, a Ford Motor Co. executive.

He plans to start his new work in earnest next week, according to Cho. They had an introductory phone conversation.

Meanwhile, Trump said he can be patient with North Korea.

"I have greater patience than any human being in the world," Trump said in an interview with Bloomberg News at the White House. "People don't understand that about me."

He reiterated that he and the North's young leader are on good terms.

He emphasized there have been no missile and nuclear tests by the North, especially since their Singapore summit on June 12.

 But he said the situation may alter down the road.

"I've had a good relationship with Kim Jong-un, and I'm not saying it won't change," he said "It could change. The whole situation could change." (Yonhap)