US Secretary of State Mike Pompeo will depart for his third trip to North Korea on July 5, the White House announced on Monday.
Pompeo will visit Pyongyang for two days before heading to Tokyo to meet with South Korean and Japanese officials, said US State Department spokesperson Heather Nauert.
"We're continuing to make progress," White House press secretary Sarah Sanders said at Monday's press briefing.
Pompeo last visited Pyongyang in May ahead of the Trump-Kim summit and travelled there secretly in early April while he was director of the CIA.
The planned visit comes amid reports that North Korea has been secretly expanding a major missile plant, potentially suggesting that the country doesn't plan to fully divest itself of its nuclear ambitions.
But Sanders said last month's historic Singapore summit between President Trump and North Korean leader Kim Jong Un has already produced a solid framework for future negotiations.
"In the last eight months, you haven't seen missile launches, you haven't seen nuclear detonations," Sanders added. "Again, these conversations are continuing to evolve -- I'm not going to get into the details, but I can tell you that progress continues to be made."
After leaving Tokyo, Pompeo will then make brief visits to Hanoi and Abu Dhabi before arriving in Brussels on July 10 for the NATO Summit.
Pompeo and President Trump are expected to discuss "burden sharing" and "defense spending" at the summit, Nauert said.
The trip will be the first of its kind since US President Donald Trump met with North Korea top leader, Kim Jong Un, in Singapore on June 12, when they issued commitment to the denuclearisation of the Korean Peninsula.
However, Pompeo's visit to Pyongyang means that the originally scheduled July 6 India-US 2+2 dialogue with India will be postponed.
The state department's announcement comes days after Pompeo called External Affairs Minister Sushma Swaraj to inform her about his decision to postpone the July 6 India-US 2+2 dialogue in Washington DC.
The department did not offer any explanation for the sudden postponement, except for saying that it was due to unavoidable circumstances.