Seol, South Korea ? North Korea said today it would not dismantle its nuclear weapons program until the United States first provides an atomic energy reactor, casting doubt on its commitment to a breakthrough agreement reached at international arms talks.

The North insisted during arms talks that began last week in Beijing that it be given a light-water reactor, a type less easily diverted for weapons use, in exchange for abandoning nuclear weapons. The agreement reached at the talks’ end Monday – the first since the negotiations began in August 2003 – says the six countries in the negotiations will discuss the reactor issue “at an appropriate time.”

Both the United States and Japan, members of the six-nation disarmament talks, rejected the North’s latest demand.

“This is not the agreement that they signed and we’ll give them some time to reflect on the agreement they signed,” U.S. State Department spokesman Sean McCormack said in New York, where he was with Secretary of State Condoleezza Rice at meetings of the U.N. Security Council.

The Beijing agreement called for the North to abandon it arms efforts and accept inspections by the International Atomic Energy Agency in exchange for energy and economic and security aid.

But the North’s statement today indicated it was again raising the reactor demand as a prerequisite for disarming.