South Korean President Moon Jae In, standing next to North Korean leader Kim Jong Un, was beaming as their talks ended Friday with the release of a joint declaration confirming the "complete" denuclearization of the Korean Peninsula as their shared goal.

But the pathway toward ridding North Korea of its nuclear weapons remains elusive, with the inter-Korean summit offering little clues as to the degree of the North's denuclearization commitment ahead of the first-ever talks between U.S. and North Korean leaders.

"We had a historic meeting and reached a valuable agreement," Moon told reporters following his talks with Kim on the southern side of the border village of Panmunjeom -- the first inter-Korean summit in over 10 years -- adding that the realization of a nuclear-free Korean Peninsula through "complete denuclearization" is their common goal.

In contrast, Kim did not specifically refer to the word "denuclearization" during the joint press announcement, although he vowed to "thoroughly implement" the just-adopted Panmunjeom Declaration aimed to ensure peace and prosperity of the peninsula.

For Moon, the joint document apparently represented a successful outcome as one of his priorities was to affirm North Korea's determination to denuclearize to lay the groundwork for talks between U.S. President Donald Trump and Kim that is expected to take place within about a month.

 (Korea Summit Press Pool)

But some experts indicated that the declaration hardly addresses the lingering doubts over how serious North Korea is about giving up its nuclear weapons following its past history of broken promises.

"Words like 'complete denuclearization' and 'a nuclear-free Korean Peninsula' sound clear-cut, but they lack concreteness and there was no roadmap," said Hideki Okuzono, a Japanese expert on Korean politics.

"At the same time, what was swept under the carpet was the fact that there is a gap between what denuclearization means for the United States and North Korea," the associate professor at the University of Shizuoka added.

Kim has reportedly proposed a "phased" and "synchronized" approach at his meeting with Chinese President Xi Jinping in Beijing in March, in a sign that he is seeking to secure rewards such as the easing of sanctions or the provision of economic assistance in exchange for incremental steps toward abandoning nuclear weapons.

(Korea Summit Press Pool) 

But the United States wants North Korea to take concrete actions before lifting economic sanctions and to relinquish its nuclear arms in a "complete, verifiable and irreversible" manner.

Less than a week before the inter-Korean summit talks, North Korea announced a halt to its nuclear and long-range missile tests as well as a shutdown of its nuclear test site, in what became the first concrete move since it expressed in March its readiness to hold denuclearization talks with the United States.

The Panmunjeom Declaration welcomed the "very meaningful" measures initiated by North Korea, but, again, left largely vague the key issue of whether the North actually has an intention to surrender its existing nuclear weapons, Okuzono said.

Rather than focusing on coming up with concrete steps toward denuclearization, North Korea appeared to be devoting itself to portraying Kim as an "open-minded and considerate young new leader of North Korea" on the occasion of the inter-Korean summit, which has drawn worldwide attention and was partly broadcast live.

Based on the live footage, Kim appeared to pay due respect to the South Korean president, who is around twice his age, and even communicated the outcome of the talks directly toward the Western media, which is something previous North Korean rulers have never done.

"Until recently, Mr. Kim had been a figure veiled in secrecy and I think many had an image of him as a dictator who could go so far as executing his uncle. But in just one day, I think that image has completely changed (in a positive way)," Okuzono said.

"In the context of dealing with the United States, it is very important to win the support of the South Korean public, and North Korea's image strategy was quite skillful," he said.

While uncertainties remain over whether the United States and North Korea can bridge their differences to strike a nuclear deal, Ken Jimbo, an expert on security issues in Japan, said even a clearer commitment by North Korea toward disarmament may not necessarily promise a breakthrough.

(Korea Summit Press Pool)

North Korea has justified its possession of nuclear weapons, touting them as a "treasured sword" to defend against the "hostile policies" of the United States and its allies.

Therefore, a security guarantee from the United States is seen as a prerequisite for the North to agree to give up its nuclear arms. But the matter is sensitive because it could lead to the undermining of the so-called nuclear umbrella that the United States has put up over its allies and also affect the existence of some 28,500 U.S. troops stationed in South Korea.

"If North Korea makes a clear commitment to denuclearization, it means that the United States will be urged to promise something in return in a tangible form that may include reducing the U.S. nuclear threat and or curbing conventional weapons...but none of those things can be changed easily," Jimbo, a professor at Keio University, said.

With the focus now shifting to the meeting between Trump and Kim, he warned that a breakdown of the talks could mean a return to a tense situation on the Korean Peninsula.

"North Korea may go back to conducting nuclear and missile tests in that case," the professor said, adding, "I'm afraid that a breakdown of the talks may lead to the conclusion that diplomacy will no longer work on the issue, although, in general, conducting a military strike against North Korea is a very difficult decision to make."

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