The North Korean leader also said his relationship with Trump remains excellent and that he will wait until the end of the year for the US to make a courageous decision regarding their negotiations to dismantle the North's nuclear weapons program in exchange for sanctions relief.

"I agree with Kim Jong Un of North Korea that our personal relationship remains very good, perhaps the term excellent would be even more accurate, and that a third Summit would be good in that we fully understand where we each stand," Trump wrote on Twitter.

"North Korea has tremendous potential for extraordinary growth, economic success and riches under the leadership of Chairman Kim. I look forward to the day, which could be soon, when Nuclear Weapons and Sanctions can be removed, and then watching North Korea become one of the most successful nations of the World!" he added.

US Secretary of State Mike Pompeo also said he is "confident" the two countries will make progress in their nuclear negotiations, adding that they have "continued to have conversations" even after the Hanoi summit.

"Chairman Kim made a commitment. He made the commitment to me personally no fewer than half a dozen times and to President Trump that he wanted to denuclearize," Pompeo told reporters during a news conference in Paraguay on Saturday. "We have work to do, but I am confident we'll continue to make progress."

Trump and Kim agreed at their first summit in Singapore last June to work toward complete denuclearization of the Korean Peninsula in exchange for security guarantees for Pyongyang.

In February, they held a second summit in Vietnam, but failed to produce any agreement. The breakdown was attributed to a gap between US demands for complete denuclearization and North Korean demands for significant sanctions relief.

In his speech Friday, Kim said he will not hesitate to sign an agreement with the US, but only if it is written in a way that meets the interests of both countries and is "fair" and "mutually acceptable." (Yonhap)