North Korea conducted an underground nuclear test on October 16 this year, after which the UN passed a resolution barring trade in dangerous weapons with Pyongyang.
 
Russia would need to guarantee any uranium it imported from North Korea would be used for peaceful purposes.
 
North Korea has boycotted talks on its nuclear weapons programme for more than a year.
 
Mohamed El Baradei, head of the International Atomic Energy Agency, has said that North Korea would need "incentives" in order to return to the negotiations "and to show the necessary flexibility".
 
El Baradei's comments came after Kim Kye-Gwan, the North Korean vice-foreign minister, said Pyongyang would not unilaterally abandon its nuclear weapons programme.