This picture taken on September 3, 2017 and released by North Korea
This picture taken on September 3, 2017 and released by North Korea's official Korean Central News Agency (KCNA) on September 4, 2017 shows North Korean leader Kim Jong-Un attending a meeting with a committee of the Workers' Party of Korea about the test of a hydrogen bomb, at an unknown location. North Korea said it detonated a hydrogen bomb designed for a long-range missile on September 3 and called its sixth and most powerful nuclear test a "perfect success", sparking world condemnation and promises of tougher US sanctions. / AFP PHOTO / KCNA VIA KNS / STR / South Korea OUT / REPUBLIC OF KOREA OUT ---EDITORS NOTE--- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO/KCNA VIA KNS" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS THIS PICTURE WAS MADE AVAILABLE BY A THIRD PARTY. AFP CAN NOT INDEPENDENTLY VERIFY THE AUTHENTICITY, LOCATION, DATE AND CONTENT OF THIS IMAGE. THIS PHOTO IS DISTRIBUTED EXACTLY AS RECEIVED BY AFP. / (Photo credit should read STR/AFP/Getty Images)
PHOTO: STR/AFP/AFP/Getty Images
Now playing
02:27
What's bringing Kim Jong Un to the table
PHOTO: Nicolas Asfouri/Pool/Getty Images/AFP PHOTO/KCNA VIA KNS
Now playing
01:27
North, South Korean leaders to meet again
PHOTO: Airbus Defense and Space
Now playing
01:44
New images show N. Korea dismantling test site
PHOTO: CNNI
Now playing
00:40
Pompeo dismisses N. Korea's 'gangster' comments
SINGAPORE - JUNE 12: In this handout photo, North Korean leader Kim Jong-un shakes hands with U.S. President Donald Trump during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore. U.S. President Trump and North Korean leader Kim Jong-un held the historic meeting between leaders of both countries on Tuesday morning in Singapore, carrying hopes to end decades of hostility and the threat of North Korea
SINGAPORE - JUNE 12: In this handout photo, North Korean leader Kim Jong-un shakes hands with U.S. President Donald Trump during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore. U.S. President Trump and North Korean leader Kim Jong-un held the historic meeting between leaders of both countries on Tuesday morning in Singapore, carrying hopes to end decades of hostility and the threat of North Korea's nuclear program. (Photo by Kevin Lim/THE STRAITS TIMES/Handout/Getty Images)
PHOTO: Handout/Getty Images AsiaPac/Getty Images
Now playing
01:56
Kim Jong Un snubbed Mike Pompeo, source says
WASHINGTON, DC - MAY 09:  National Security Adviser John Bolton speaks on a morning television show from the grounds of the White House, on May 9, 2018 in Washington, DC. Yesterday President Donald Trump announced that America was withdrawing from the Iran nuclear deal.  (Photo by Mark Wilson/Getty Images)
WASHINGTON, DC - MAY 09: National Security Adviser John Bolton speaks on a morning television show from the grounds of the White House, on May 9, 2018 in Washington, DC. Yesterday President Donald Trump announced that America was withdrawing from the Iran nuclear deal. (Photo by Mark Wilson/Getty Images)
PHOTO: Mark Wilson/Getty Images
Now playing
01:34
Bolton: US has plan for denuclearizing N. Korea
PHOTO: Planet Labs Inc.
Now playing
01:25
Satellite images show missile plant construction
PHOTO: CNN
Now playing
01:14
Susan Rice: Kim Jong Un beat Trump at summit
Images of the Norrth Korea missile launch on November 28 taken from Rodong Sinmun, North Korea
Images of the Norrth Korea missile launch on November 28 taken from Rodong Sinmun, North Korea's official newspaper.
PHOTO: From Rodong Sinmun
Now playing
02:14
Will North Korea restart nuclear tests?
PHOTO: Photo Illustration/Getty Images
Now playing
03:00
Will Kim Jong Un ever give up his nukes?
PHOTO: Photo Illustration/Getty Images
Now playing
02:27
What's bringing Kim Jong Un to the table
Now playing
01:51
Who is Kim Jong Un?
PHOTO: CNN
Now playing
01:43
Connolly: Trump comment on Kim 'jaw-dropping'
Now playing
02:31
Moon: The masterful dealmaker
Trump Kim Jong Un comment 04240218
Trump Kim Jong Un comment 04240218
PHOTO: CNN
Now playing
01:26
Trump: Kim Jong Un very open and honorable
Now playing
03:06
Finding art on the edge of the DMZ
(CNN) —  

When North Korean leader Kim Jong Un and his South Korea counterpart, Moon Jae-in, meet next Friday, the most important topic on the agenda is the one on which there has been least clarity: denuclearization.

The term has been bandied about in recent weeks, from Seoul to Washington to Beijing, yet there’s little agreement on what the term means – and confusion could lead to trouble in this week’s summit as well as the planned meeting between US President Donald Trump and Kim.

South Korean officials and Chinese state media have said Kim is willing to discuss denuclearization on the Korean Peninsula.

On Thursday, President Moon announced North Korea had not raised its long-running demand for the withdrawal of US forces in exchange for giving up nuclear weapons – an apparent concession that analysts greeted with skepticism.

“North Korea has been saying all the right things … they want this summit to occur and they’re doing what it takes to make it happen,” said Adam Mount, a senior fellow at the Federation of American Scientists.

So far, North Korean state media has made no mention of the topic, and public statements by Kim have been vague.

“It is our consistent stand to be committed to denuclearization on the peninsula, in accordance with the will of late President Kim Il Sung and late General Secretary Kim Jong Il,” Kim said in Beijing on March 27, according to Chinese state news agency Xinhua.

It elicited a positive response from US President Donald Trump, who said there was now a “good chance” of denuclearization by North Korea.

But are Trump, Kim and Moon talking about same thing when it comes to North Korea giving up its nuclear capabilities?

Denuclearization: What the US and South Korea mean

Over the past decade, denuclearization in North Korea has only ever meant one thing for the United States and South Korea.

“It’s called CVID – complete, verifiable, irreversible dismantlement of the North Korean program,” said Josh Pollack, senior research associate at the Middlebury Institute of International Studies at Monterey.

The language has been used consistently by the United Nations Security Council in its resolutions condemning North Korea as far back as October 2006.

“Irreversible,” in the practical sense, aims to ensure the current facilities cannot be reactivated after they’ve been dismantled, Pollack said.

Any denuclearization deal would need to include a series of “verifiable” steps for dismantling North Korea’s program, carried out under the eyes of independent observers, former Australian Prime Minister and diplomat Kevin Rudd told CNN in March.

“Unless there is independent monitoring … any unilateral undertakings by the North Koreans will probably not be worth the paper they’re written on,” he said.

Inspections could be carried out by an international body such as the International Atomic Energy Agency (IAEA) whose inspectors were previously expelled by North Korea in 2002.

For decades, the US and South Korea have pushed for denuclearization in North Korea.

In 1991, Pyongyang joined Seoul in signing a “joint declaration of the Denuclearization of the Korean Peninsula.” Two years later, North Korea pledged it would dismantle its nuclear program in exchange for international aid.

But every time promises weren’t delivered and pledges not followed through on both sides, leading to disappointment and suspicion.

Still, the US government appears hopeful the latest round of talks will be different. Trump on Wednesday offered a bullish view, insisting he’s positioned to accomplish what his predecessors could not.

However, he said he’d be willing to stand up and leave the highly anticipated summit should the meeting fall short of his expectations.

On South Korea’s part, Moon denied on Thursday there was any separation between what the North and the South meant by denuclearization. “I do not think there is any difference in the concept,” he said.

Denuclearization: What North Korea means

When North Korean leader Kim Jong Un promised talks on denuclearization in Beijing in March, according to Xinhua, he didn’t speak of Pyongyang ending its program. He spoke of “denuclearization on the (Korean) Peninsula.”

“To Kim, denuclearization applies to the whole peninsula, which includes the South,” David Maxwell, retired US Army Special Forces colonel and a fellow at the Institute of Korean American Studies, told CNN in March, prior to Moon’s statement on Thursday.

Experts said Pyongyang has long been expected to push for American military presence across the border to be part of the discussion, a position Pollack said he wasn’t sure had changed despite the South Korean’s president’s remarks.

Although the US hasn’t stationed nuclear weapons in South Korea since 1992, Pollack said North Korea considered the US’s mere presence on the peninsula a nuclear threat.

“They really are threatened by superior American and South Korean military power, they need nuclear weapons to try and prevent an invasion in their view,” Pollack said.

“They feel the need to equate their nuclear program with the (US and South Korean) military alliance and claims the military alliance is a nuclear threat, when there’s no real grounds for that.”

Experts said North Korea’s apparent change of heart on the US military presence in South Korea seemed at best a temporary concession or, at worst, an attempt to drive a wedge between Washington and Seoul.

“The pessimistic interpretation is that Kim is intent on making concession after concession in private to show Moon that he is the reasonable one, with the expectation that Trump will ultimately be unable or unwilling to deliver,” Pollack said.

’Pie in the sky’

Experts told CNN the confusion over how much each side was willing to give and what their basic goals were for the summits make a positive outcome harder to see.

Adam Cathcart, an expert on North Korea at the University of Leeds in the UK, said the hopes of some officials in Washington that Kim would willingly give up his nuclear weapons program were “utopian, really pie in the sky.”

Speaking to CNN in March, Cathcart said given the ongoing “disdain” the Trump administration had shown for the Iran deal reached during President Barack Obama’s administration, it was hard to see a similar, incremental plan getting support in Washington.

The deal removed many of the sanctions on the Iran government, in exchange for the Middle East country getting rid of the majority of its weapons program and uranium – a key ingredient for nuclear weapons.

The reality, argue analysts, is there simply too much distrust and too little understanding between the two sides to come to an agreement.

“They will affirm the principle of denuclearization as they did in 2005,” said Pollack. “And the implementation will be drawn up and never happen,” he said.

CNN’s Joe Sterling, James Griffiths and Jamie Tarabay contributed to this article.