In the last run-up to our special pre-summit reports from the perspective from regional players... and today,... we turn to the U.S.,... who await their own summit with North Korea sometime in June.
It's still unclear as to what we can expect from the Trump-Kim meeting,.... but what we know for sure... is that a successful inter-Korean summit will have to come first.
Our Kwon Jang-ho has more.
When South Korea's National Security Advisor visited the White House in early March few anticipated what would happen next.

"He expressed his eagerness to meet President Trump as soon as possible. President Trump appreciated the briefing and said he would meet Kim Jong-un by May"

"When President Trump suddenly accepted Kim Jong-un's invitation to meet, Washington was caught off guard. Although there’s been some time to digest this move, opinions and hopes for the U.S.-North Korea summit remain mixed."

Trump's seemingly unilateral decision to hold talks as soon as possible has turned the traditional order of diplomacy upside down. The extensive negotiations that normally take place before leaders meet has been cut short.

"There is very little that I think those of us who have been in the world of diplomacy would call normal about the upcoming meeting... I find it hard to believe they can go far down the road in substance. There may be general agreement but general agreement in the past between the DPRK and the USA hasn't been such a terrific idea, without details laid on and the verification and the monitoring laid on with those details."

However, there are some who argue that it could prove to be the spark that moves things forward.

"It is the opposite pattern of the way that diplomatic negotiations are normally conducted. However there is a tradition, especially in Asia, of the sort of big men getting together, having a cup of tea, sort of sorting things out and leaving the details to their subordinates. That's what I see from these two individuals."

"Everyone and their cousin would say do it the other way around, have all the diplomats first and the summit is the cherry on the top, the summit meeting the two leaders comes last. On the other hand, we've been doing it that way for 65 years and nothing has changed on the Peninsula."

For a successful meeting, experts agree that South Korea has a crucial role to play in its own summit with the North.

"One hopes that the South Koreans are able to make some progress in setting the stage for a US-DPRK discussion on denuclearization. And it would be great if there was a direct reference to denuclearization as part of what President Moon and Kim Jong un are able to agree upon."

"The inter-Korean process is and needs to be central if we're going to get someplace. And one of the things that I actually find most significant and hopefully encouraging about what's going on now is that the Republic of Korea has played such an important role as a catalyst and as a shaper."

With so many uncertainties, expe