US President Donald Trump said on Friday that his summit with North Korean leader Kim Jong Un later this month will be held in Vietnam's capital, Hanoi.

The US president said US diplomats had a "very productive meeting" with North Korean officials in Pyongyang to prepare for the summit.

"My representatives have just left North Korea after a very productive meeting and an agreed upon time and date for the second Summit with Kim Jong Un. It will take place in Hanoi, Vietnam, on February 27 & 28," Trump said on Twitter.

"I look forward to seeing Chairman Kim & advancing the cause of peace!" he said.

Earlier this week, Trump announced that he would be meeting Kim in Vietnam, but he did not disclose the city.

The planned Hanoi summit follows on from an unprecedented meeting between the leaders in Singapore last June. Then, Kim pledged to work toward the "complete denuclearization" of the Korean Peninsula, without providing a clear timetable or roadmap.

Read more: 2019: Will there be a breakthrough on the Korean Peninsula?

'Hard work' still needed

The progress on North Korea giving up its nuclear weapons program has been negligible amid differences between the two sides.

Stephen Biegun, the US special representative for North Korea who led the preparatory talks in Pyongyang, said last week that the talks would be aimed at seeking progress on commitments made in Singapore and mapping out "a set of concrete deliverables" for the second summit.

"Our discussions were productive," Biegun said after the three-day meeting in the North Korean capital.

"[President Trump] is very much looking forward to taking next steps. We have some hard work to do with DPRK between now and then. I am confident if both sides stay committed we can make real progress here," he said, referring to North Korea by its formal name, the Democratic People's Republic of Korea.

The US State Department said in a statement that Biegun and Kim Hyok Chol, North Korea's special representative for US affairs, agreed to meet again before the leaders' second summit.

Biegun is thought to have discussed specific disarmament steps that Pyongyang could promise at the planned summit and what corresponding measures Washington is willing to take.

ap/aw (AP, Reuters, AFP)

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