Trump's impulsive tendencies
The United States President first offered to meet Mr Kim Jong Un during his election campaign. "What the hell is wrong with speaking? And you know what? It is called opening a dialogue," Mr Donald Trump told Reuters in a 2016 interview. He went on to suggest that he would serve the North Korean leader "a hamburger on a conference table".
After taking office, he again raised the possibility of meeting Mr Kim, saying in May last year he would be honoured to meet him "under the right circumstances".
But these overtures were drowned out by the bellicose war of words between the two men as Pyongyang stepped up the pace of missile testing to perfect its technology last year. Just two months back, Mr Trump tweeted that the US nuclear button is "much bigger and more powerful" than North Korea's. It was a response to Mr Kim's mention of his nuclear button in his New Year message.
A tweet or a perceived slight by either man could throw a spanner in the works.
The fine print
Washington and Pyongyang are poles apart in their positions on the nuclear issue: The Trump administration wants a nuclear weapons-free North Korea, but Pyongyang sees its missile and nuclear programme as a guarantee of regime survival.
Ms Duyeon Kim, a visiting senior research fellow at the Korean Peninsula Future Forum, wrote that the parties involved have different understandings of "denuclearisation", "threat" and "security". "The Trump administration, Seoul, and Tokyo will only accept complete denuclearisation by North Korea, while Kim Jong Un desires arms-control talks between two nuclear powers on an equal footing," she wrote in the Bulletin of Atomic Scientists.
If Trump-Kim talks do take place and begin to address denuclearisation, it is still unclear what the US would ask for in terms of extent and verification, or what North Korea would ask for in terms of regime security.
"Such requests would be hard for Washington to accept if they involve a change to the US defence architecture in Asia or its security relationship with allies such as Japan and South Korea," Stratfor said in its analysis of the planned talks.
Who will lay groundwork for the talks?
Concerns are growing that there is too little time to prepare for what would be the first summit between sitting American and North Korean leaders.
Such a summit would typically happen after each side had made at least some concrete agreements, said Ms Suzanne DiMaggio, a senior fellow at the New America think-tank.
"It will have to be managed carefully with a great deal of prep work," she said on Twitter.
Mr Trump himself has no experience or expertise in foreign policy. And the State Department has seen an exodus of veterans, the latest being Mr Joseph Yun, the US point man in charge of negotiating with the North.
Tay Hwee Peng