North Korea on Monday lifted its ban on U.N. inspections of the plutonium-producing plant it used to set up an atomic test blast and announced it will resume deactivating a linked facility within days, the International Atomic Energy Agency said.

The moves were revealed in a restricted IAEA document to its 35-nation board of governors that was obtained by The Associated Press. They were a strong indication that the country was making good on its pledge to return to an international deal meant to strip its weapons-enabling nuclear program in exchange for political concessions and energy aid. Pyongyang announced Sunday it would resume dismantling its atomic program after the United States removed North Korea from its list of states sponsoring terrorism.

"The agency inspectors were ... informed today that as of 14 October 2008, core discharge activities at the [nuclear] reactor would be resumed," said the two-paragraph document. It said all activities envisioned in the "monitoring and verification arrangements" agreed on between the U.N. nuclear agency and the North would also resume.

North Korea set off a nuclear test blast in 2006, then agreed to dismantle its nuclear program in exchange for the concessions.

But negotiations have foundered and up to late last week, the North had threatened to reactivate the plutonium reprocessing plant at the Yongbyon site, telling International Atomic Energy Agency inspectors to remove IAEA seals and banning U.N. inspectors from the sprawling site. It also stopped deactivating the nuclear reactor at Yongbyon.

Despite the ban, the three-member IAEA team was allowed to stay on at their guest house in Yongbyon. And one diplomat told The Associated Press on Monday that the government approved visas late last week for members of a new inspection team — even as it appeared to be moving to restart its atomic activities.

The diplomat is based in Vienna, home to the IAEA, and is familiar with the agency's monitoring activities at Yongbyon, but was not authorized to release the information and spoke to The Associated Press on condition of anonymity.

That suggested that the North's threat to stop dismantling its nuclear program and restart it was a negotiating ploy meant to wrest more concessions from the U.S., Russia, China, South Korea and Japan, the five countries engaging the reclusive communist country.

On Monday, South Korea said it is considering expanding cross-border projects now that international standoff appears to have ended over the communist country's nuclear program, an official said Monday.

Kim Ho-nyeon, a spokesman at South Korea's Unification Ministry, told reporters Monday that South Korea is considering "adjusting" various projects, such as its food aid to the impoverished North.

He did not elaborate but his office later explained that South Korea has long sought to expand inter-Korean economic projects and humanitarian aid to the North in tandem with progress in the nuclear issue.

Meanwhile, about 70 conservative activists called on the U.S. to withdraw its delisting decision in a rally Monday near the American Embassy in Seoul.

Chanting "We oppose the terror delisting," the activists tried to burn signs with photos of North Korean leader Kim Jong Il, triggering a minor scuffle with police.

Relations between the divided Koreas have worsened since a conservative, pro-U.S. government was inaugurated in Seoul in February with a pledge to get tougher on the North. Pyongyang has cut off government-level contacts with the South in retaliation.