Oct. 3 (Bloomberg) -- The U.S. said North Korea must submit to international inspections of its nuclear sites, as envoy Christopher Hill continued talks in Pyongyang today aimed at salvaging the disarmament process.

Six-party negotiations have been deadlocked since mid- August due to a dispute over how to check the extent of North Korea's nuclear weapons program.

Agreement on a verification protocol is an ``irreducible component of the six-party process moving forward,'' State Department spokesman Sean McCormack told reporters in Washington yesterday. The plan before the North Koreans includes an ``inspection component,'' he said.

Hill, who arrived in the North Korean capital two days ago, is trying to break a deadlock in disarmament talks, also involving China, Russia, Japan and South Korea. Kim Jong Il's regime, which tested a nuclear device in 2006, says international inspections would violate the country's sovereignty.

Hill yesterday extended his visit to Pyongyang by a day. He is scheduled to return to Seoul later today for talks with his South Korean counterpart Kim Sook and Japanese counterpart Akitaka Saiki, who is flying in from Tokyo. Hill is then scheduled to fly to Beijing for talks with Chinese officials, McCormack said.

Yongbyon Reactor

The communist state stopped disabling the Yongbyon reactor, the source of its weapons-grade plutonium, in mid-August to protest delays in being removed from a U.S. terrorism blacklist. Last week it expelled United Nations inspectors from the plant.

The Bush administration has said the regime will remain on the list until a verification system is in place.

The U.S. and its partners must be able to assure themselves that North Korea's declaration of its nuclear program, made in a dossier submitted in June, is ``full and complete and verifiable,'' McCormack said.

One option for breaking the deadlock is giving China, a close ally of North Korea and chair of the six-party talks, a more prominent role in the verification efforts, the New York Times reported, citing an unidentified Bush administration official. North Korea would submit its list of nuclear sites to China, rather than to the U.S., though would still have to permit inspections by both countries, according to the report.

North Korea signed the six-party disarmament accord in February 2007 and pledged to disable its nuclear program in return for energy aid and normalized diplomatic ties with the U.S. and Japan.

Kim's regime shut down the Yongbyon reactor last year and in June blew up a cooling tower at the plant. A South Korean Foreign Ministry official said this week North Korea may be able to restart operations at Yongbyon's nuclear material reprocessing plant within three months.

Kim's Health

The deadlock in the disarmament talks comes amid speculation about Kim's health. U.S. and South Korean intelligence officials said last month that he may have had a stroke, sparking concerns about potential instability in North Korea.

The state's official Korea Central News Agency last noted a public appearance by Kim when it reported on his inspection of the nation's army on Aug. 14. Kim's 50 day absence from the public eye is the longest stretch since 2003, when he quit the nuclear Non- Proliferation Treaty and didn't have any public engagements for 49 days, the Unification Ministry in Seoul said today.

To contact the reporters on this story: Ed Johnson in Sydney at ejohnson28@bloomberg.net; Heejin Koo in Seoul at hjkoo@bloomberg.net

Last Updated: October 3, 2008 01:25 EDT