North Korea must suspend its nuclear weapons program immediately to show it is taking negotiations on disarmament seriously, the United States said on Thursday on the second day of six-party talks in Beijing.
Negotiators said the three-day session would focus on the logistics of further bargaining after a framework for disarmament was agreed in September, but the perennial issue remains trust between the two main protagonists, Washington and Pyongyang.
"The time to stop that reprocessing, the time to stop the reactor, is now," chief U.S. negotiator Christopher Hill told, referring to the North's nuclear plant at Yongbyon.
U.S. Ambassador to South Korea Alexander Vershbow said on Wednesday the United States would be willing to open an office in Pyongyang as a gesture of goodwill, but Hill stressed that goodwill should be reciprocal.
"The point the U.S. ambassador to South Korea was making was that the DPRK has to establish a level of trust. They're often fond of talking of our level of trust but they have some responsibilities themselves," he said, referring to the North by its official name, the Democratic People's Republic of Korea.
The United States says the plant at Yongbyon has continued to operate since the September 19 joint statement, in which North Korea agreed to dismantle its nuclear programs in exchange for aid and security guarantees.
The agreement was seen as a breakthrough, but tough questions remain over the timing of concessions and the North's demands for a light-water reactor for atomic energy.
Japanese envoy Kenichiro Sasae said Thursday's sessions would focus on implementation after the North on Wednesday reaffirmed its intention to scrap its nuclear programs, Reuters reports.