North Korea announced Thursday that it is preparing to restart the facility that produced its atomic bomb, clearly indicating that it plans to completely pull out of an international deal to end its nuclear program.

North Korea told the International Atomic Energy Agency that it was stopping the process of disabling its main nuclear site and barring international inspectors from the Yongbyon facility, the agency said.

Pyongyang "informed IAEA inspectors that effective immediately access to facilities at Yongbyon would no longer be permitted," the U.N. nuclear watchdog said.

North Korea "also stated that it has stopped its (nuclear) disablement work," its statement said.

"Also, since it is preparing to restart the facilities at Yongbyon, the DPRK has informed the IAEA that our monitoring activites would no longer be appropriate," the statement said, referring to the north by its formal acronym.

But the statement said the IAEA's small inspection team would remain on the site until told otherwise by North Korean authorities.

Pyongyang already barred agency personnel from its plutonium reprocessing facility at Yongbyon last month after telling them to remove IAEA seals from the plant in a reversal of its pledge to disable its nuclear program in return for diplomatic concessions and offers of energy aid.

But Thursday's statement was the clearest indication to date that the North planned to abrogate the deal, said a senior diplomat linked to the IAEA who demanded anonymity because he was not authorized to comment to the media.

The North was to eventually dismantle the complex in return for diplomatic concessions and energy aid equivalent to 1 million tons of oil under a February 2007 deal with the U.S., South Korea, China, Russia and Japan.