Secretary of State Condoleezza Rice says North Korean steps this week related to its nuclear weapons are positive - but that more cooperation is needed in the future. VOA's Kurt Achin reports from Seoul, where she is meeting with the South Korean President and key foreign policy ministers.

U.S. Secretary of State Condoleezza Rice during news conference in Seoul, 28 Jun 2008

Secretary of State Condoleezza Rice says North Korea needs to be more forthcoming about its nuclear past. 

During Saturday's visit to the South Korean capital, she said documents Pyongyang has provided to the United States include some references to a suspected highly enriched uranium, or HEU, program.  They also partially address North Korea's activities to help other countries develop nuclear technology.  But Rice says what the North has provided is not enough.

"Concerning those two issues - HEU and proliferation -  I have said before and I will say again, that we don't have the answers that we need about either, but I expect that the North will live up to the obligation that it has undertaken to take those concerns seriously and to address them."

The United States believes North Korea helped Syria build a nuclear production facility, which Israeli warplanes bombed earlier this year.

North Korea submitted an overdue declaration of its nuclear production this week, as part of multinational negotiations aimed at ending its nuclear capabilities altogether.  It deals mainly with North Korea's production of plutonium, concentrated at its Yongbyon facility.

In May, North Korea turned over thousands of pages of operating records from Yongbyon to the United States.  On Friday, in a highly symbolic public display, the North blew up the facility's cooling tower.

S. Koreans watch television broadcasting demolition of N. Korea's cooling tower at its main nuclear reactor complex, 27 Jun 2008

What North Korea has not yet done is clarify how many nuclear weapons it has, and where they are.  Rice says those tasks, are to be accomplished at future rounds of multinational talks.

"Let me just emphasize again - at the end of this, we have to have the abandonment of all programs, weapons, and materials," she said.

Separately, Rice said protests over the resumption of U.S. beef imports will not harm the two countries' relationship.  She says Washington will continue to cooperate with South Korea to build consumer confidence in the safety of U.S. beef, and to ratify a much broader two-way trade liberalization deal.  Police in the South Korean capital braced Saturday for another weekend of street demonstrations against the import resumption.