South Korea said Friday it is continuing to monitor North Korea, but declined to confirm or deny a report citing alleged evidence that the communist nation is preparing for an underground nuclear test.
"We are monitoring movements in North Korea in preparation for any possibility of a nuclear test," Lee Yong-joon, head of the South Korean Foreign Ministry's task force on the North Korea nuclear issue, told The Associated Press. He declined to comment directly on the report about a possible test, citing protocol.
The United States and South Korea "share all intelligence and evaluations" related to North Korean movements, Lee said.
South Korea's spy agency, the National Intelligence Service, also declined to comment directly on the report.
"We cannot specifically confirm the report as it is an intelligence matter," a spokesman said on condition of anonymity, citing policy.
The comments came after the U.S. television network ABC quoted an unidentified State Department official as saying a North Korean nuclear test was "a real possibility."
The report also cited an unidentified senior U.S. military official as saying that a U.S. intelligence agency recently had seen "suspicious vehicle movement" at a suspected test site, including the unloading of reels of cable outside an underground facility in northeast North Korea.
Such cables are connected to outside monitoring equipment and could be a possible sign of an upcoming test. The report said the White House was told about the intelligence last week.
The White House declined to confirm the report, but an official there who refused to be identified said Washington's position was that a "North Korean nuclear test would be an extremely provocative action that would draw universal condemnation from the international community."
North Korea has claimed to have nuclear weapons, but has not conducted any known test that would confirm it has been able to successfully build an atomic bomb. A June report from the Washington-based Institute for Science and International Security said the North had enough radioactive material to build between four and 13 bombs.
U.S. officials said in May 2005 that they detected possible signs of a nuclear test, citing construction of a tunnel and a reviewing stand, but nothing more happened at that time.
The North test-fired seven missiles last month over international objections, drawing U.N. Security Council sanctions. No progress has been made since then on the impasse, and the North has refused to return to international talks on its nuclear programs that have been stalled since November.
A researcher with links to the South Korean intelligence community said Friday that "caution is needed" when dealing with observations of activity inside North Korea because their intentions are often unclear, declining to comment directly on the latest report.
He said it was too early to say whether a test was imminent from a single piece of information, noting that equipment to measure radioactivity and seismic activity, as well as excavators, would have to be in place for a nuclear test.
Also, people would have to be evacuated from near the possible test site, he said, speaking on condition of anonymity because of the sensitivity of his position.