"We are disappointed and concerned over the DPRK's decision to suspend the disablement of nuclear facilities and consider reactivating its Yongbyon reactor," a ministry statement said.
"This means an unnecessary pause in the denuclearization of the Korean Peninsula and the possibility of a step backward."
Russia also urged Pyongyang to complete the closure of its nuclear facilities in Yongbyon, as was agreed at the six-party talks on the Korean Peninsula nuclear issue on July 12.
"We are urging the DPRK to display true commitment to the verifiable denuclearization of the Korean Peninsula, continue the disablement of the nuclear facilities in Yongbyon and complete this process by the end of October this year," the statement said.
According to media reports, the DPRK said earlier Tuesday that it would stop disabling its nuclear facilities and consider restoring the Yongbyon nuclear reactor, which is a plutonium-producing facility, because the United States had not kept its promise of removing Pyongyang from its terror blacklist.
The United States said it was not going to remove the DPRK from its list of terrorism sponsors due to a lack of a strong inspection regime for its nuclear program.
Under an agreement reached at the six-party talks in Beijing last February, the DPRK agreed to abandon all nuclear weapons, declare all its nuclear programs and disable the existing nuclear facilities by the end of 2007 in exchange for diplomatic and economic incentives.
