U.S. President Donald Trump said on Monday that he is "not ready" to travel to North Korea, although he declined to comment on a media report that the country's leader Kim Jong Un had invited him to Pyongyang.

Asked by reporters at the White House following the South Korean newspaper report whether he is willing to visit North Korea, Trump said "probably not," although he emphasized that his relationship with Kim is "very good."

"I would do it...at some time in a later future and depending on what happens. I'm sure he'll love coming to the United States also. But no, I don't think it's ready for that, I think we have a ways to go yet," the president said.

The two leaders have held three rounds of face-to-face talks so far, the most recent in June at the Demilitarized Zone dividing the two Koreas. They agreed to restart the stalled talks on North Korea's denuclearization and invited each other to visit their capital cities.

Citing diplomatic sources, South Korean newspaper Joongang Ilbo reported Monday that Kim had conveyed his willingness to host Trump in Pyongyang in a letter sent to the president in the third week of August.

Diplomatic sources familiar with the situation later confirmed that Kim conveyed his desire to invite Trump in his letter.

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