North Korea has once again denied it has a uranium-based nuclear weapons program.

According to diplomatic sources, North Korean officials denied enriching uranium for use in nuclear weapons during recent talks with U.S. State Department official Sung Kim.

Kim, who heads the department's Korea Desk, visited Pyongyang last week to discuss the declaration of the North's nuclear programs.

Sources say North Korea admitted to importing 140 tons of aluminum tubes from Russia. But it insisted they were used to make rocket bombs, not nukes

In Tokyo, a Japanese daily reported Sunday that North Korea’s top nuclear negotiator Kim Kye-kwan had hinted to his Chinese counterpart that his country's declaration would cover only plutonium-based activities.