North Korea has begun reassembling its main nuclear facility in violation of agreements it made to give up its nuclear programmes, a Japanese and US news report said.
Japan's Kyodo News agency cited unnamed diplomatic sources in Beijing for its report Wednesday that said the work at the nuclear centre in Yongbyon, 100 kilometres north of the capital, Pyongyang, had begun Tuesday.
The report came one week after North Korea announced it had stopped disabling the nuclear facility in mid-August to protest the US failure to remove the country from its list of state sponsors of terrorism, reported dpa.
It had also warned that it was considering restoring its Yongbyon facilities to their original state.
Unnamed US officials cited in the report by the Fox News network in the United States said they believed the motive behind the reassembly was also anger at the US delay in taking North Korea off the terrorism list.
The United States has demanded more stringent verification measures to check whether North Korea is keeping its nuclear promises before taking it off the list.
Pyongyang accused Washington of failing to keep its side of a deal struck to end North Korea's nuclear programmes. In response, North Korea said it would not keep its side of the agreement.
The Yongbyon facility includes a nuclear reactor, which can produce plutonium, which can be used to produce nuclear weapons.
Fox News said reassembling the facility was seen as a "symbolic gesture" because the North Koreans had already broken down so much at the Yongbyon centre, but one US official told Fox that the reactor could be operational again in two to three months.
In a deal made in six-nation talks with Russia, China, South Korea, Japan and the United States, North Korea first shut down its facilities at Yongbyon in July 2007 and was working to disable them, or render them impossible to use, before finally dismantling them.
In return, it is to receive energy and economic aid and the United States and Japan are to work to normalize their relations with the Stalinist state. The United States vowed to remove the communist state from its list of countries sponsoring terrorism and lift trade sanctions.
Dismantlement began last autumn, and in a new round of six-nation talks in July, North Korea had promised to complete that work by October.
A joint statement at the end of those talks said the participants had agreed to develop a verification mechanism to achieve a nuclear-free Korean Peninsula. Talks on implementing that part of the agreement, however, have stalled.
The developments of the past two weeks represented a turnaround for North Korea, which in June demolished the cooling tower of its Yongbyon nuclear reactor is a symbolic gesture meant to convey its intention to live up to the six-nation agreements.