The United States and North Korea have agreed to blow up the cooling tower at the North’s key nuclear facility in Yongbyon. Its destruction would kick off the final phase of the North's nuclear dismantlement.

South Korea’s top nuclear envoy Kim Sook confirmed the agreement while speaking to reporters in Washington on Tuesday. The remarks came after a meeting earlier in the day with his U.S. and Japanese counterparts.

Kim said the North had conveyed verbally to the U.S. details of its nuclear declaration when State Department official Sung Kim visited Pyongyang twice last month and earlier this month.

Kim says Washington expects to finish analyzing within a few weeks some 18-thousand pages of documents on the North's nuclear activities. He said the North is likely to make its nuclear declaration at the end of the month if the results of the document analysis are positive.