Donald Trump said he didn't have time to include in his agreement with Kim Jong-un guarantees that North Korea's disarmament would be "verifiable and irreversible".

He also didn't have time to discuss the issue of a peace treaty with the South. "I'm here one day," he retorted when pressed by journalists about why the letter the two leaders had signed seemed to lack detail. But he did have time to show a four-minute film to Kim and his entourage on an iPad.