He added that he was hopeful of progress in the latest round of negotiations that first began more than three years ago.
 
"If we're successful we could get to the point where we are discussing technical matters at working groups," he said.
 
Several rounds of six-party talks have yet
to produce significant progress [AFP]
 
The Asahi Shimbun quoted US and North Korean sources as saying that the North had agreed to shut down its nuclear reactor at Yongbyon and allow UN inspections of its nuclear plants.
 
In return, the paper said, the US had pledged energy and humanitarian assistance.
 
North Korea's envoy meanwhile has said he is prepared to disciss "first stage measures" of nuclear disarmament, but said any moves would be determined by the attitude of the US side.
 
"We are going to make a judgment based on whether the United States will give up its hostile policy and come out toward peaceful coexistence,'' said Kim Kye-gwan.
 
The US, he said, was "well-aware" of what it had to do, adding there were still "many points of confrontation to resolve".
 
Persuasion
 
North Korea's envoy says there are many
issues of confrontation to overcome [AFP]
Although the US led calls for United Nations sanctions in the wake of North Korea's first nuclear weapon test last October, it has since engaged in a series of diplomatic moves to persuade the North to disarm.
 
Since 2003, the six-party talks have produced only a single agreement - a 2005 plan under which the North agrees to abandon its nuclear programme in return for aid and pledges that Washington would not seek to topple the government.
 
Implementing that plan, however, has proved the sticking point.
 
At the last round of talks held in Beijing in December North Korea insisted no progress could be made without the lifting of US financial sanctions.
 
The US, for its part, says the sanctions must be dealt with as a separate issue.
 
Negotiators said it was important to take the first steps towards bringing the plan into reality at this week's talks, which bring together China, Japan, Russia, the United States and the two Koreas.
 
"When we do get a set of actions, or if we do, it will widely be seen as a very solid positive step for the implementation of the September agreement, with the understanding that there is no success till we implement the full agreement," Hill said.
 
No deadline has been set for this round of talks, but Hill said the Chinese hosts expected the talks to last a few days and the sides would start reviewing a draft agreement on Friday.