Delegations from five nations are arriving in Beijing for this week's start of a new round of negotiations on North Korea's nuclear programs.
Members of the North Korean and other delegations arrived at Beijing airport on Saturday and Sunday, and made no comments as they walked past reporters.
China is hosting the third round of six-way negotiations involving officials from Japan, North Korea, Russia, South Korea and the United States.
Working-level discussions begin Monday, before high-level negotiations get under way later in the week. Officials from the United States and other countries were holding consultations on Sunday.
The United States demands that North Korea dismantle its nuclear weapons programs in a complete, verifiable and irreversible manner. North Korea says it will freeze its plutonium program in exchange for economic assistance and security guarantees.
The standoff started about a year-and-a-half ago, and analysts are not predicting any substantial progress during these talks. The first round, held in August, ended only with a promise to meet again. The second round in February led to the establishment of working groups that have met once over the past four months.
The dispute flared in October 2002, when the United States said North Korea admitted to restarting its plutonium enrichment program in violation of a 1994 freeze. Pyongyang says it is developing what it calls a nuclear deterrent force, to defend itself from what North Korean officials claim is a planned U.S. invasion.
The United States has said it does not plan to invade North Korea. U.S. officials have ruled out giving in to North Korean demands for aid, in exchange for a nuclear freeze. Washington says it will not reward the reclusive North Korean state for merely fulfilling its international obligations.