The DPRK has "immediately started the work of removing the seals and monitoring cameras from the frozen nuclear facilities for their normal operation to produce electricity", said the Korean Central News Agency (KCNA).
This means the DPRK's call to the International Atomic Energy Agency (IAEA) on Dec. 14 to remove surveillance facilities had turned into reality.
The KCNA reiterated that the DPRK's decision to lift the freeze of its nuclear facilities was a follow-up to the suspension of heavy oil supply by the United States, and it accused the US of "escalating international pressure " on the DPRK in settling the nuclear issue.
The DPRK's decision is a serious step to safeguard its sovereignty and vital rights from the US, the KCNA added.
The US decided on November 14 to suspend heavy oil supply to the DPRK as a sanction over its uranium enrichment program in violation of the Agreed Framework reached by the two sides in 1994.
Under the Agreed Framework, the DPRK was to stop its nuclear facilities in return for two light water reactors and 500,000 tons of heavy oil a year from the US.