According to Mike Pompeo, US President Donald Trump has made the decision not to sign a joint statement with North Korea.
Pompeo added that a date hasn't been set for next working-level meeting on North Korea, because it may take a little while as both sides need to regroup.
"We haven't set a date. My sense is it will take a little while, we'll each need to regroup a little bit. But I'm very hopeful that Special Representative Biegun and that team will get together before too long," Pompeo said.
The US-North Korea summit in the Vietnamese capital kicked off on Wednesday with a brief meeting and a social dinner between the two leaders.
The historic US-North Korea summit 2018 concluded with a four-point declaration that paved the way toward renewed bilateral relations and the denuclearization of the Korean Peninsula.