A United States institute says that North Korea has resumed work on a light water reactor that could be used to support its nuclear programme after 'months of inactivity.
The analysis was based on satellite photographs taken on 30th April showing new construction at the Yongbyon site.
According to the institute, it may take one to two more years before the site is fully operational.
Officials said both the light water reactor and enrichment plant were meant to produce power for civilian use.
But experts said the reactor could be used to produce plutonium and the plant could be converted to produce highly enriched uranium for weapons.
News of progress on the reactor site comes amid reports that North Korea may be planning to carry out a third nuclear test.