VIENNA–North Korea barred UN monitoring throughout its Yongbyon nuclear complex on Thursday in a significant step towards scrapping a deal with five powers to scrap its atomic bomb programme, diplomats said.
"The monitors were told that as of today, they are out, no more access permitted to any facilities in Yongbyon. But as of now, they are still in their guest house on the premises," a senior diplomat close to the International Atomic Energy Agency told Reuters.
The diplomats, who asked not to be identified because they were not authorized to speak publicly on the confidential matter, said the Vienna-based UN nuclear watchdog was likely to make an announcement later in the day.
North Korea acted exactly two years after its first nuclear weapon test which alarmed the world and led to crisis diplomacy leading to a groundbreaking disarmament pact in February 2007.
Two weeks ago the reclusive Stalinist state expelled the monitor team from Yongbyon's plutonium-producing plant, kernel of its atom bomb capability, and vowed to start reactivating the Soviet-era facility shortly.
At the time, Pyongyang let the IAEA continue verifying the shutdown status of other parts of Yongbyon. The IAEA's tools included surveillance cameras and seals placed on equipment.
The Yongbyon complex includes the reprocessing plant where bomb-grade plutonium can be extracted from spent fuel rods, a fuel fabrication facility and a five-megawatt reactor.
The nuclear disarmament pact North Korea struck with five regional powers appeared to unravel last month after Pyongyang, angry at not being removed from a U.S. blacklist of sponsors of terrorism, vowed to rebuild the largely dismantled Yongbyon.
Washington said it would take the North off the list, bringing economic and diplomatic benefits, once a system had been agreed to verify its statements on its nuclear programme.
"North Korea is trying to strengthen its position," Paik Hak-soon, director at South Korea's Center for North Korean Studies, said of Pyongyang's decision to put all of Yongbyon facilities off-limits to the IAEA.
"This is a follow-up to the decision to restore the nuclear facility ... It is something happening in the tug-of-war with the United States," he said.
Kyodo news agency, quoting Japanese government sources, said Washington had told Tokyo it would remove North Korea from the blacklist this month. There was no immediate official comment.
Diplomats had said the next critical step for North Korea towards reviving Yongbyon would be removing IAEA seals from thousands of fuel rods in storage to prepare for reintroducing them into the reprocessing plant.
"The monitors were there (at storage sites) but from here on they are out. So the IAEA won't know what the North Koreans are doing any more," said the senior Vienna diplomat.
South Korea on Tuesday played down unconfirmed reports that North Korea delivered an ultimatum when it held talks last week with a visiting U.S. envoy trying to save the floundering deal to denuclearize the Korean peninsula.
U.S. Assistant Secretary of State Christopher Hill has given no details of three days of talks he had in Pyongyang last week. He said the focus of the discussions was on finding a way to verify what the North said about its nuclear programme.
Diplomats and analysts tracking the issue say it could take North Korea between three months and a year or more to reverse the disablement of its nuclear infrastructure.