Tokyo: The US chief negotiator on North Korea says he expects Pyongyang to shut down its nuclear reactor in about three weeks after he paid a rare visit to the communist state.

North Korea promised in a six-nation deal in February to shut down its Yongbyon reactor in exchange for aid and diplomatic benefits. But it has refused to comply due to a long-running row over frozen funds.

Christopher Hill, the US pointman on North Korea, said that inspectors from the International Atomic Energy Agency would arrive next Tuesday, which the UN watchdog confirmed Friday in Vienna. "Predictions are hard in this business, but I think what will happen is next week the international inspectors will come in," Hill told CNN in an interview yesterday from Seoul, during a regional tour. "Then I think within the week after that, or within two weeks of that, I think we can expect a shutdown of this facility," Hill said. "When it does, it will be a good day."

Hill said that the row over the frozen assets was effectively settled, with the North Koreans either having received or about to receive the money through a bank account in Russia.

Hill on Thursday and Friday held talks with senior officials in North Korea, the first such visit by a US negotiator in nearly five years. "One of the reasons I saw the North Koreans was to make sure we have got our signals right and we are going to proceed on this," Hill said. "I think they are set to shut it down and they confirmed that to me."

The Yongbyon reactor is the source of raw material for bomb-making plutonium in North Korea, which tested an atom bomb last year.