With his historic meeting Tuesday in Singapore with North Korean leader Kim Jong Un, U.S. President Donald Trump has begun a high-stakes venture to end decades of hostility with North Korea and remove its nuclear and missile threats against the United States and allies South Korea and Japan.

With Kim pledging to work toward the "complete" denuclearization of the Korean Peninsula and Trump committing to provide security guarantees to North Korea, Pyongyang is likely to step up its calls for replacing a Korean War armistice with a peace treaty that would formally end the 1950-1953 conflict.

"While the armistice was agreed to, the war never ended, to this day never ended," Trump told reporters after the first-ever U.S.-North Korea summit. "But now we can all have hope that it will soon end."

[Kevin Lim/THE STRAITS TIMES/Handout]

Analysts warn, however, that Trump has little room for mistakes. If Washington and Pyongyang sign a peace treaty first, the incentive for North Korea to rid itself of nuclear weapons and their delivery systems -- including short- and medium-range missiles capable of hitting South Korea and Japan -- would be squandered.

"It would be a real mistake to have a peace treaty come first, then denuclearization, because that is clearly an open admission that you're dealing with North Korea as an acknowledged nuclear weapon state," said Joseph Yun, a former U.S. special representative for North Korea policy.

The armistice -- signed by the U.S.-led United Nations Command, North Korea and the Chinese People's Volunteer Army -- has left the main combatants technically in a state of war.

Robert Gallucci, a former U.S. nuclear negotiator with North Korea, voiced a similar view, saying legitimizing a North Korean nuclear weapons program "would be a mistake in terms of our own security, the security of our allies, in terms of the incentives for Seoul and Tokyo to remain non-nuclear weapons states, and for the whole regime of nonproliferation."

Others point out that signing a peace treaty with North Korea would undermine the rationale for the U.S. troop presence in South Korea.

"You can have a peace declaration saying, 'OK. Let's have peace.' You can even open liaison offices" in Washington and Pyongyang for a regular conduit of communications, said Sue Mi Terry, senior fellow for Korea at the Center for Strategic and International Studies, a Washington think tank.

But concluding a peace treaty should come after North Korea dismantles its nuclear weapons program, Terry said. "That should be at the end of the process, not at the beginning."

Given that complexity, Yun said a peace treaty, which Trump said should also involve South Korea and China, is "way more than just a treaty, and which is why I think it's going to take so long."

"There are many issues there," he said. "I think it's going to be complicated."

Given what appears to be a lengthy process and Pyongyang's apparent stance of wanting to manage -- not eliminate -- its nuclear capabilities, some analysts suspect Kim may be extending an olive branch to Trump in an attempt to win sanctions relief for a freeze of the weapons programs, while in the process buying time to make a nuclear-armed North Korea a fait accompli.

Looking into the past, North Korea has a track record of using denuclearization talks to extract aid and other concessions while covertly continuing development of nuclear weapons and ballistic missiles.

Despite Trump's promise of security guarantees to North Korea, many find it difficult to imagine Kim would bargain away the nuclear arsenal it has developed over decades. It does not make a lot of sense for Kim to suddenly abandon "the state nuclear force" he claimed to have completed just last year, either.

In reference to the U.S. midterm elections in November and Trump's expected bid for re-election in 2020, Douglas Paal of the Carnegie Endowment for International Peace suggested there is no need for Kim to rush to make a deal with Trump, especially when international economic and diplomatic pressure on North Korea could already be weakening as Kim courts China and South Korea.

"We have elections and the North Koreans just have to worry about the leader's health," said Paal, vice president for studies at the Washington think tank. "If you don't have an election coming up, you'd rather see it go on and on, and then let the process get muddied down the road in the hopes of hanging on to as much of your capability as you can in the process."

Paal said North Korea seems to be looking at India as an example of winning a de facto nuclear status while developing relations with the United States through cooperation in civil nuclear energy. But he said Washington is unlikely to buy such a scenario.

Michael Green, a former national security adviser for Asia to President George W. Bush, said that rather than the so-called India model, North Korea may be looking to Pakistan, another de facto nuclear state, as a viable case to emulate.

"They'd like something maybe a little closer to what you might call the Pakistan model, where we're not cooperating with them on nuclear issues and energy peacefully, as we are with India, but we just don't give them a hard time," such as imposing sanctions, Green said. "But I don't think they're going to get that either."