IAEA approves atom bomb shutdown mission to N.Korea

"This is the beginning of (what is) going to be a long and complex process," ElBaradei cautioned.

After throwing out U.N. inspectors in 2002, North Korea quit the Non-Proliferation Treaty (NPT), which the IAEA enforces. In 2005, Pyongyang declared it had nuclear arms, and unnerved the world with a test-detonation a year later.

The IAEA verification task is only an "ad hoc arrangement," not a normal, full-fledged inspections regime. That would have to be negotiated later as part of a new Safeguards Agreement to bring North Korea back into the NPT.

North Korea agreed on February 13 to close Yongbyon and take steps to disable all its nuclear facilities in exchange for 950,000 more tonnes of fuel oil or aid of equivalent value.

Elbaradei put the cost of the IAEA monitoring mission at 1.7 million euros ($2.3 million) for 2007 and 2.2 million euros in 2008 and said the IAEA was assured of getting extra-budgetary funds for the task from various donors.

Diplomats said U.S. and European Union envoys pledged at least some of the money at the board meeting with Japan, Russia, China and South Korea likely to chip in the rest if needed.

Earlier on Monday, the board approved an IAEA budget of 295 million euros ($402 million) for 2008 after agency planners cut a requested rise from 2 percent to 1.4 percent above inflation.

ElBaradei said the deal was "far from adequate" at a time of rising nuclear proliferation challenges like Iran.