The chief U.S. envoy to the talks praised the breakthrough as a "win-win situation" and "good agreement for all of us. But he promptly urged Pyongyang to make good its promises by ending operations at its main nuclear facility at Yongbyon.
"What is the purpose of operating it at this point?" said U.S. Assistant Secretary of State Christopher Hill. "The time to turn it off would be about now."
Despite the deal's potential to help significantly ease friction between the North and the United States, after years of false starts and setbacks, Hill remained cautious.
"We have to see what comes in the days and weeks ahead. We have to seize the momentum of this," he said before leaving for the airport to return to Washington.
"The breakthrough agreement with North Korea not only diffuses a two-year stalemate but holds out the hope that Pyongyang will return to its international treaty obligations," said CBS News foreign affairs analyst Pamela Falk, "with a gradual normalization of relations as part of the agreement.
"There still is a lot of negotiating that will have to be completed in November, including the specifics of the agreements and time frames," added Falk, "but in essence, North Korea has agreed to end its existing nuclear weapons and ongoing development and to include inspections in exchange for a U.S. agreement not to invade or attack North Korea and to gradually normalize relations. When nuclear weapons are eliminated, a peaceful nuclear energy program would be considered and, in the meanwhile, the other five parties to the talks agreed to provide energy assistance."
The agreement takes the pressure off the United Nations with regard to North Korea and avoids a contentious debate about sanctions at a time when talks with North Korea had stalled."
The agreement clinched seven days of talks aimed at setting out general principles for the North's disarmament. Envoys agreed to return just over a month later, in early November, to begin hashing out details of how that will be done.
According to a joint statement issued at the talks' conclusion, the North "committed to abandoning all nuclear weapons and existing nuclear programs and returning at an early date" to the Nuclear Nonproliferation Treaty and International Atomic Energy Agency safeguards.
"The six parties unanimously reaffirmed that the goal of the six-party talks is the verifiable denuclearization of the Korean Peninsula in a peaceful manner," the statement said.