The North rather expressed confidence about its nuclear force, which leader Kim Jong-un declared as complete in November after a slew of weapons tests that included the underground detonation of a purported thermonuclear warhead and flight tests of three intercontinental ballistic missiles.
The announced action comes less than a week before Kim meets South Korean leader Moon Jae-in for a summit in the Demilitarized Zone (DMZ) between the two rival countries and ahead of an anticipated meeting in the near future between Kim and Trump.
"North Korea has agreed to suspend all Nuclear Tests and close up a major test site", POTUS tweted.
Trump on Friday welcomed the statement, saying he looked forward to a summit with Kim.
North Korea has defended its nuclear and missile programmes in the face of worldwide condemnation and sanctions as a necessary deterrent against perceived U.S. hostility. But North Korea for decades has been pushing a concept of "denuclearization" that bears no resemblance to the American definition, vowing to pursue nuclear development unless Washington removes its troops from the peninsula.
It remains to be seen what exact conditions will need to be met for the withdrawal of global economic sanctions aimed at ending North Korea's nuclear threat.
"If I think that it's a meeting that is not going to be fruitful, we're not going to go", Trump said during a news conference with Japanese Prime Minister Shinzo Abe in Florida. "This is the party's new strategic policy line".
Kim Song-nam, vice head of the party's worldwide affairs, who accompanied the leader on his March trip to Beijing, was chosen as a member of the committee and North Korean Sports Minister Kim Il-guk, who spearheaded inter-Korean sports exchanges, became an alternate member.
It sent a delegation to the Winter Olympics held in South Korea.
"I don't know exactly how they'll go about it", he said. "But, like with all positive first steps we've had in North Korea negotiations, it can still very easily reverse".
He has served as the director and chief secretary of the National Defense Commission Secretariat, Kim Jong-un's executive office.