Had 'very substantive' negotiations with Kim, says Trump

US President Donald Trump announced that he held "very substantive negotiations with Kim Jong Un" at the recently concluded Hanoi summit - which ended abruptly without a joint agreement on Thursday.

"Great to be back from Vietnam, an amazing place. We had very substantive negotiations with Kim Jong Un - we know what they want and they know what we must have. Relationship very good, let's see what happens!" Trump tweeted on Friday (local time).

Expectations were high from the now-concluded second summit between North Korea and the United States at Vietnam. However, the two-day meeting ended abruptly on Thursday after the sides failed to reach an agreement to chart out the future steps towards the denuclearisation of North Korea - as promised by the reclusive state during the first US-North Korea summit in Singapore last year.

North Korea sought partial relief in sanctions at the summit in Vietnam, according to Pyongyang's Foreign Minister Ri Yong Ho. The United States, however, has reiterated its stand to ease sanctions only when complete denuclearisation is reached.