The Democratic People's Republic of Korea (DPRK) has invited nuclear experts from the United States, China and Russia to survey its nuclear facilities, the chief U.S. nuclear negotiator said in Sydney Friday.

U.S. Assistant Secretary of State Christopher Hill said the team of experts will go to the country Tuesday for an initial four-day survey tour.

He made the announcement during a briefing on activities of U.S. President George W. Bush, who is here attending the economic leaders' meeting of the Asia-Pacific Economic Cooperation (APEC) forum.

"The overture is another significant step toward the denuclearization of the Korean peninsula," said the U.S. official.

Hill said the invitation from the DPRK was a result of a U.S.-DPRK meeting in Geneva last weekend.

The experts will engage in discussions on the scope and technical feasibility of disabling the nuclear facilities, Hill said, adding that a full review of the facilities will hopefully be completed by Dec. 31.

Under a deal reached in February after years of negotiations, the DPRK agreed to abandon its nuclear programs in exchange for duel and other aid.

The United States agreed in return to open talks on establishing normal diplomatic relations with the DPRK.

Asked by reporters earlier this month on whether the United States would remove the DPRK from a list of states accused of sponsoring terrorism in reward for the nuclear declaration and disablement, Hill said he did not want to get "more specific."

The DPRK had repeatedly demanded its removal from the list which is considered a key element in the relationship between the two countries that have been enemies for 50 years.

The United States and the DPRK held two-day meeting in Geneva early this month. After the meeting, Hill told a press conference "One thing that we agreed on is that the DPRK will provide a full declaration of all of their nuclear programs and will disable their nuclear programs by the end of this year, 2007."

Hill said his talks with DPRK Vice Foreign Minister Kim Gye Gwan had been "very good and very substantive," which provided a better chance of success for the next round of six-party negotiations aimed at denuclearization of the Korean Peninsula.

Besides the United States and the DPRK, the six-party negotiations also involve China, the Republic of Korea, Japan and Russia.