U.S. Secretary of State Mike Pompeo hopes that “real and substantive” progress will be made during the upcoming second summit between the U.S. and North Korea.

The secretary expressed cautious optimism on Sunday regarding the outlook of the summit during an interview with “Fox News Sunday,” saying he hopes the two nations will take a step forward, but that the two sides "may not get everything done this week." 

Pompeo said another summit might be needed, citing U.S. President Donald Trumps' recent remarks, and that members of his team are working towards developing a "roadmap" for the two countries. 

In regards to the Hanoi summit, Pompeo said it could be held for one or two days.