SEOUL, Jan. 30 (Yonhap) -- South Korea expressed regret to North Korea Thursday over its reported progress in its nuclear weapons programs and pressed again for Pyongyang to give up the programs.
"It is very serious and regrettable that North Korea makes progress in its nuclear programs," unification ministry spokeswoman Park Soo-jin said.
She made the comment hours after the top U.S. intelligence official said North Korea expanded the size of its Yongbyon enrichment facility and restarted the reactor that was previously used for plutonium production.
"We assess that North Korea has followed through on its announcement" director of National Intelligence James Clapper said Wednesday in a written statement to the Senate Intelligence Committee.
He was referring to Pyongyang's announcement to "adjust and alter" the uses of existing nuclear facilities to include the uranium enrichment facility at Yongbyon, and restart its graphite moderated reactor.
In October, the National Intelligence Service, South Korea's top spy agency, told lawmakers that the North restarted its Yongbyon reactor that had been mothballed since 2007.
The reactor, located 90 kilometers north of Pyongyang, has been cited for producing plutonium for the North's nuclear weapons program before it was shut down under a deal brokered at the six-nation nuclear talks six years ago. The North had blown up the reactor's cooling tower in 2008 to show its seriousness about suspending operations.
In Washington, Clapper also said North Korea has taken initial steps toward fielding its KN08 road-mobile intercontinental ballistic missile, though it remains untested.
"North Korea is committed to developing long-range missile technology that is capable of posing a direct threat to the United States," Clapper said in a written testimony
Also Wednesday, 38 North, a website specializing in North Korea-related news run by the U.S. Korea Institute of Johns Hopkins University, said a possible test of a rocket engine used by the KN08 took place between late December 2013 and early January, citing satellite images.
"Imagery from late December indicated the presence of what appears to be a rocket stage consistent with the KN08 ballistic missile's first stage and possibly a crane that would be used to place the engine into the test stand and remove it after a test," the website said.
The website said imagery taken two weeks later showed that the rocket stage and other equipment were gone.
In October, the National Intelligence Service told lawmakers that the North conducted an engine test for a long range rocket at its Tongchang-ri launch site on the west coast.
The U.S. website said North Korea may be preparing the Tongchang-ri launch site for a more robust rocket test program in the future involving larger space launch vehicles and road-mobile ballistic missiles, citing recent satellite images.
The gantry tower "has been undergoing significant modifications to enable it to launch a large rocket up to 25 percent longer than the Unha-3 space launch vehicle tested in 2012," the website said.
It added that the pad will not be available for launches until March or April this year at the earliest due to construction.
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