North Korea threatened Tuesday to use nuclear weapons at "any time" against the U.S., saying that its atomic program is a response to a "reckless hostile policy" from Washington.
The state-run Korean Central News Agency said that the North's nuclear program had been "steadily improved" by scientists and technicians. It added that uranium enrichment and the reactor at the Yongbyon nuclear facility -- which had been shut down under an agreement reached in the six-party talks in 2007 -- had been restarted in 2013.
Pyongyang had said previously that work had resumed at Yongbyon, but the status of the plant's operation had been questioned by foreign analysts off and on for the past year.
Satellite imagery published last week by the North Korea affairs website 38 North suggested evidence of new activity at Yongbyon's plutonium production complex. Yongbyon is about 55 miles north of Pyongyang, the capital.
Tuesday's statement came a day after North Korea claimed to be in the final phase of developing a new earth observation satellite.
"The world will clearly see a series of satellites of [North] Korea soaring into the sky," said a report by the state-run news agency.
Pyongyang has alluded to the possibility of launching a satellite on Oct. 10, a holiday on which it will mark the 70th anniversary of the founding of the ruling Workers' Party.
By ratcheting up its rhetoric, the North Korean government could be attempting to drum up popular support before that day's celebrations. "It's likely that they're trying to build patriotism before the holiday on Oct. 10," said Kim Bo-geun, a North Korea analyst at the Hankyoreh Unification Institute in Seoul.
North Korea is barred by U.N. Security Council resolutions from carrying out any launches that use ballistic technology. South Korea's Ministry of National Defense said in a briefing on Tuesday that it had not detected signs of an imminent launch.
The two consecutive days of aggressive statements from Pyongyang could dampen the mood of North-South rapprochement that was created after the two sides agreed to end a crisis that saw an exchange of fire across their border last month.
After days of meetings in August, high-ranking officials reached an agreement whereby Pyongyang expressed regret for a mine explosion earlier in the month that injured two South Korean soldiers, and Seoul agreed to halt loudspeaker propaganda broadcasts it had launched in response.
At those meetings, the two countries also agreed to work to hold reunions for families that were divided by the 1950-53 Korean War. The reunions are now being planned and scheduled to go ahead Oct. 20-26, but could be scuttled if North Korea does launch a satellite on Oct. 10.
North Korea steadfastly claims that its satellite program is an exercise of its right as a sovereign state to explore space. But for its domestic audience, it depicts its satellite programs as necessary for national security.
"The launches play into their militarism -- this idea that they're facing an external, specifically American, threat, but are developing the capacity to face that down," said Sokeel Park, director of research and strategy at Liberty in North Korea, a nongovernmental organization that works with recently escaped North Korean defectors.
Launched in 2003, the six-party talks were aimed at ending North Korea's nuclear program through negotiations. The discussions involved China, the United States, North and South Korea, Japan, and Russia. But the talks collapsed six years ago and have not been restarted.
Borowiec is a special correspondent.
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