Foreign Minister Yu Myung-hwan said Wednesday "the last work" on the process was under way, which could lead to the six-party talks among the United States, Russia, China, Japan and the two Koreas to resume as early as next month, Yonhap news agency reported.

China's Xinhua news agency reported the U.S. team, led by Sung Kim, director of the Korean desk at the U.S. State Department, arrived in Pyongyang Tuesday to discuss North Korea's declaration of its nuclear programs, which is the next step in the denuclearization effort.

The U.S. team drove across the 38th parallel from Panmunjom, the heavily guarded border between the two Koreas, to proceed to Pyongyang, Xinhua said.

The talks reportedly would deal with verifying the North's disclosure of its nuclear programs. The visit comes after the North announced this month an agreement with the United States on the declaration.

The talks have been stalled over U.S. claims that the North's prior document did not include declaration of its plutonium stockpiles, alleged uranium enrichment program and suspected nuclear cooperation with Syria, which the North denies.

"North Korea is expected to submit a declaration before the end of this month, if the U.S. team's activity goes well," a South Korean government source told Yonhap.