North Korea could shut down its plutonium-producing reactor within three weeks, a top US nuclear envoy said on Saturday after returning from a rare visit to the secretive communist nation.

Christopher Hill—the chief US negotiator at international talks on North Korea’s nuclear programmes—also told reporters in Tokyo that the next round of negotiations could begin in early July, before a full shutdown of the Yongbyon reactor.

Hill said the reactor would be closed after North Korea and the UN’s nuclear watchdog agree on how to monitor the process. UN inspectors are to arrive in North Korea on Tuesday.

“We expect this to be ...within three weeks... but I don’t want to be pinned down on precisely the date,” Hill said, after briefing his Japanese counterpart Keni-

chiro Sasae on the outcome of his trip to Pyongyang.