The United States says North Korea has slowed down some of its nuclear disablement activities.

The head of the US State Department's Office of Korean Affairs, Sung Kim, has just returned from North Korea with 18,000 documents about its nuclear program.

He says it is an important first step in getting Pyongyang to give up its nuclear ambitions, but says the pace of that work is being deliberately drawn out.

"I believe they have slowed down the pace a bit and they have cited the need to sort of coordinate the timing with energy assistance," he said.

The North Korean documents do not cover their alleged enrichment of weapons grade uranium and suspicion that Pyongyang has shared nuclear technology with Syria.

New aid proposal to combat famine
The United States says it is working on a new proposal to send emergency food aid to North Korea.

A State Department spokesman, Sean McCormack, says no agreement has been reached but the US is studying a report from its experts who held "inconclusive" talks last week in Pyongyang.

He did not confirm or deny a report in the Financial Times that the United States has agreed to the delivery of 500,000 tons of food aid in return for unprecedented access for monitors who would oversee its distribution.

The State Department says the provision of food aid depends on the level of need, supply and its ability to ensure that the aid reaches the people in need.

Produced by Radio Australia and Australia Network