The Democratic People's Republic of Korea (DPRK) said on Friday it is making "thorough preparations" to restart its nuclear reactor, accusing the United States of failing to fulfill its obligations under an international disarmament-for-aid agreement.

It is the first time Pyongyang has confirmed it is reversing steps taken earlier to disable its nuclear program, although it had previously threatened to do so because of Washington's refusal to remove it from a US terrorism blacklist.

"We are making thorough preparations for restoration" of the Yongbyon nuclear complex, Hyun Hak-bong, deputy director-general of the DPRK's foreign affairs ministry, told reporters.

Hyun spoke to reporters in the border village of Panmunjom before sitting down for talks on Friday with Republic of Korea officials on sending energy aid to the DPRK as part of the six-nation disarmament deal.

Under the landmark 2007 pact - also involving China, Russia and Japan - the DPRK pledged to disable its nuclear program in a step toward its eventual dismantlement in exchange for diplomatic concessions and energy aid equivalent to 1 million tons of oil.

The DPRK began disabling the Yongbyon complex last year. Major progress was made in late June when the DPRK submitted a declaration of its nuclear activities and destroyed the cooling tower at Yongbyon.

But the accord ran aground in the middle of last month when Washington refused to take the DPRK off its list of states that sponsor terrorism until the DPRK accepts a plan to verify its nuclear declaration.

Pyongyang responded by halting the disabling process and is now "proceeding with work to restore (Yongbyon) to its original status", Hyun said.

Hyun warned Washington not to press the verification issue, saying verification was never part of the disarmament deal.

Liu Jiangyong, a professor at Tsinghua University, said Pyongyang's latest move does not mean the Six-Party Talks have failed.

Pyongyang has taken the step in response to the changing international situation, he said. As both the US and Japan are electing their new leaders, Pyongyang has decided to take a hard-line stance, Liu said.

(China Daily/Agencies September 20, 2008)