The president has told a number of TV anchors about the meeting plans between him and Kim, police said just before Trump was to hold his speech on the state of the kingdom. A few hours later he confirmed this information when he met in Congress and held the speech known as the State of the Union speech.
The meeting Kim and Trump in Vietnam will be the second time they meet in under one year. In June, Singapore hosted the first ever meeting between a North Korean leader and a seated US president.
A delegation led by US special envoy Stephen Biegun travels to North Korea on Wednesday to prepare for the meeting between the two leaders at the end of the month.