A team from the UN's nuclear watchdog arrived in North Korea today ahead of a planned shutdown of its atomic reactor.
On arrival in Pyongyang the team from the International Atomic Energy Agency (IAEA) declined to answer questions from waiting reporters.
North Korea said last week it would consider suspending the operation of its nuclear facilities as soon as it received the first shipment of oil from South Korea under the February 13th aid-for-disarmament deal.
A South Korean tanker carrying 6,200 tonnes of fuel oil arrived earlier today at the port of Sonbong on North Korea's northeastern coast, the Unification Ministry in Seoul said.
It was the first instalment of a 50,000-tonne oil shipment North Korea is to receive in return for shutting its reactor at Yongbyon, north of Pyongyang, and admitting an IAEA team to help monitor the closure.
It will be the first time the North's nuclear activities have been under outside surveillance since late 2002.
US negotiator Christopher Hill told Japanese media he expects North Korea will produce a list of all its nuclear facilities in the coming weeks or months.
The leader of the IAEA team said earlier in Beijing they would be going straight to Yongbyon today to begin work at the complex, which produces weapons-grade plutonium.
The arrival of the UN team is a major success for negotiators involved in seemingly endless six-nation talks aimed at marks the talks aimed halting Pyongyang's nuclear arms programme.
The United States, South Korea, China, Japan and Russia have promised massive economic aid and better diplomatic ties if Pyongyang sticks to the deal.