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There is a "substantial" chance that the US-North Korea summit won't go ahead as planned on 12 June, US President Donald Trump said Tuesday. The president made the comments before meeting with the South Korean president Moon Jae-in at the White House.

The doubt was cast after North Korean officials said they would never unilaterally surrender its weapons and threatened to pull out of the summit after Trump's national security advisor John Bolton insisted the United States would work off the "Libya model" –thereby leading the North Koreans to believe this implied regime change.

Trump labeled China's President Xi Jinping a "world class poker player" and insisted that China encouraged North Korea's hardened stance to gain leverage in concurrent trade negotiations. Trump said there are conditions that North Korea must meet before the summit goes ahead, but hinted that unilateral denuclearisation may not be one of them. The president told reporters "it would certainly be better if it were all in one", but continued “does it have to be? I don’t think I want to totally commit myself".

A commemorative coin for the event was released this week by the White House Communications Agency and derided for referring to the North Korean leader as "Supreme Leader Kim Jong-un".