What happened at the Trump-Kim summit meeting?

There were contradictory accounts of how President Trump’s summit meeting with North Korea’s leader, Kim Jong-un, collapsed with no deal, their personal warmth yielding to hard disagreement.

After the talks were abruptly abandoned, Mr. Trump said he had rejected an offer from Mr. Kim to dismantle some of his nuclear program in exchange for the lifting of all sanctions. The North disputed this, saying it had asked only for some of the sanctions to be removed.

One expert suggested that there had been inadequate preparation and that both leaders were too confident in their negotiating skills.