GENEVA – North Korea agreed Sunday to account for and disable its atomic programs by the end of the year, offering its first timeline for a process long sought by nuclear negotiators, the chief U.S. envoy said.

Kim Gye Gwan, head of the North Korean delegation, said separately his country’s willingness to cooperate was clear – in return for “political and economic compensation” – but he mentioned no dates.

Hill, a U.S. assistant secretary of state, said two days of talks between the United States and North Korea in Geneva had been “very good and very substantive” and would help improve chances of a successful meeting later this month with Japan, Russia, South Korea and China in six-nation talks aimed at ending the North’s nuclear weapons program and improving relations between North Korea and other countries.

“One thing that we agreed on is that the DPRK will provide a full declaration of all of their nuclear programs and will disable their nuclear programs by the end of this year, 2007,” Hill told reporters, using the initials for the Democratic People’s Republic of Korea.

Hill said the declaration will also include uranium enrichment programs, which the United States fears could be used to make nuclear weapons.

“When we say all nuclear programs, we mean all,” he said.

He said later in response to a question from The Associated Press that it was the first time that North Korea had ever offered a timeline for declaring and disabling its nuclear program.

Kim said, “We agreed a lot of things between the United States and the DPRK. We are happy with the way the peace talks went.”

“We made it clear, we showed clear willingness to declare and dismantle all nuclear facilities,” he said.

The agreement is “very significant, for sure,” said Patricia Lewis, director of the U.N. Institute for Disarmament Research in Geneva, noting that North Korea had allowed U.N. inspectors back into the country and that they could verify what is declared.

“Confidence can increase and we can see whether or not it’s really being shut down,” Lewis said.

Hill declined to say whether the agreement would include more than the plutonium-producing nuclear reactor in Yongbyon, which North Korea shut down in July.

“We have to work out some of the details on that,” Hill told reporters. “We will have a declaration in time to disable what needs to be disabled,” he said, adding that “for example the Yongbyon reactor would have to be included.”

He said he and Kim had discussed a range of issues in their two days of talks at the U.S. and North Korean missions to U.N. offices in Geneva.

Kim said one of those was North Korea’s demand to be removed from the U.S. list of state sponsors of terrorism.

“In return for this we will receive political and economic compensation,” he said. “We wouldn’t be an enemy country anymore.”

Hill said earlier Sunday that improving U.S. relations with North Korea will depend on other progress in the talks, saying it “is a relationship that we will continue to try to build step by step with the understanding that we’re not going to have a normalized relationship until we have a denuclearized North Korea.”

He said he expected the next full session of the six-nation talks in mid-September would produce a “more detailed implementation plan for ‘disablement.'”

The meeting in Geneva was part of a flurry of “working group” sessions called for in February’s six-nation accord in which North Korea agreed to disable its plutonium-producing nuclear reactor and declare and eventually dismantle all its nuclear activities.

In exchange, the economically struggling North will receive oil and other aid. The U.S., as part of the agreement, promised to begin the process of removing the country from the terrorism list and work toward full diplomatic relations.

Daniel Pinkston, who heads the East Asia Nonproliferation Program at the Monterey, Calif.-based Center for Nonproliferation Studies, said, “I believe they’re going to do it.”

But he said it was important that North Korea declare all the uranium enrichment and plutonium stocks.

Years of tension and deadlock over North Korea’s nuclear program – which peaked with the country’s nuclear test last October – have started to ease in recent months as the talks have made progress.