Hanoi, Vietnam (CNN) North Korea asked for only a partial lifting of sanctions during a meeting this week with US President Donald Trump, Foreign Minister Ri Yong Ho said during a rare news conference early Friday morning.

Pyongyang would be willing to allow US experts to witness North Korea permanently dismantle uranium and plutonium production facilities at its Yongbyon nuclear site if the US removed partial sanctions, Ri said.

"If the US removes partial sanctions, the articles of sanctions that hamper the economy and the livelihood of our people, we will permanently and completely dismantle all the material in the nuclear material production facilities in the Yongbyon area including plutonium and uranium," he said.

Ri made the comments just hours after Trump walked away from negotiations with North Korean leader Kim Jong Un in Vietnam. The US President said he did so because North Korea demanded the removal of all sanctions levied against Pyongyang.

"Basically they wanted the sanctions lifted in their entirety, and we couldn't do that," Trump said at a news conference following the summit.

Read More