US Secretary of State Mike Pompeo is to travel to North Korea this Thursday for talks on denuclearisation of the Korean Peninsula with North Korean leader Kim Jong-un.
It will be Mr Pompeo's first visit to North Korea since the unprecedented summit between President Donald Trump and Mr Kim in Singapore last month.
Mr Trump has claimed that a statement he signed with Mr Kim at the summit resolved the old foes' nuclear stand-off, but Mr Pompeo has been tasked with nailing down details.
White House spokeswoman Sarah Sanders told a news briefing that the United States was "continuing to make progress" in talks with North Korea.
She said she would not confirm or deny recent media reporting of intelligence assessments that have cast doubt on North Korea's willingness to give up its nuclear weapons programme.
She endorsed comments on Sunday by US National Security Adviser John Bolton who said he believed the bulk of North Korea's weapons programmes could be dismantled within a year "if they have the strategic decision already made to do that".
The State Department said Mr Pompeo would leave North Korea on Saturday for Tokyo and on Sunday hold talks with both Japanese and South Korean officials.
On Sunday, he will carry on to Hanoi for talks with the Vietnamese government and the week after continue on to the Emirati capital Abu Dhabi before arriving in Brussels on 10 July.
There, he will accompany Mr Trump to a two-day NATO summit and meet European officials to discuss energy.
