Talks between the United States and North Korea on normalizing bilateral relations ended Tuesday, with both sides sounding optimistic about further discussions.

US Assistant Secretary of State Christopher Hill said he and North Korea Vice Foreign Minister Kim Kye-gwan had "very good discussions" on comprehensive topics in a businesslike atmosphere and that both sides felt optimistic that the normalization process was on the right track.

"I would say there was a sense of optimism on both sides that we will get through this 60-day period and we will achieve all of our objectives that are set out in the Feb. 13 agreement," he said, referring to an agreement reached last month at the six-party talks in Beijing that involve the United States, North Korea, South Korea, China, Russia and Japan.

Kim, for his part, said the talks were "very good, constructive and sincere."

"Wait and see about the results," the Yonhap news agency quoted Kim as saying. "If I say everything now, it would not be fun anymore."

Kim was the highest-ranking North Korea official to visit the US since 2000. He and Hill were meeting in the framework of the Working Group on Normalization of DPRK-US Relations as agreed at the third session of the fifth round of six-party talks.

The Feb. 13 agreement also called for the establishment of four other working groups -- denuclearization of the Korean Peninsula, normalization of North Korea-Japan relations, economy and energy cooperation, and Northeast Asia Peace and Security Mechanism.

Hill said the two sides spent a considerable amount of the more than eight hours together on Monday and Tuesday looking forward to the next phase, "which will be more difficult."

He stressed that North Korea should "fulfill their part of the bargain -- which is complete denuclearization" before normalization of relations.

Hill said the two sides are looking forward to "additional discussions" at the remainder of the Working Group and the six-party delegation meetings in Beijing.

"It was useful for me to hear their plans for how they will proceed to the next stage," said Hill. "So I think we also have the will to move to the next stage."

"We'll have bilateral meeting in Beijing in the framework of the six-party talks."

During their talks in New York, Hill and Kim also discussed political, legal and historic aspects in steps toward ending the designation of North Korea as a state-sponsor of terrorism and terminating the application of the US Trading with the Enemy Act with respect to North Korea.

Under the Feb. 13 document, North Korea will shut down and seal the Yongbyon nuclear facility, including the reprocessing facility and invite back IAEA personnel to conduct all necessary monitoring and verifications.

In addition, the parties also agreed to the provision of emergency energy assistance to North Korea in the initial phase, and the assistance equivalent to 50,000 tons of heavy fuel oil will commence within 60 days.

The normalization talks between the US and North Korea occurs at a time when Mohamed ElBaradei, chief of the International Atomic Energy Agency, prepares to visit Pyongyang on March 13 to discuss how to monitor its promised dismantling of nuclear facilities.

(Xinhua News Agency March 7, 2007)