A U.S. military document says North Korea poses a "traditional, irregular' and potentially "catastrophic" challenge to the international community.

The National Defense Strategy paper, which was released by the Pentagon on Friday, said insurgents in Iraq and Afghanistan presented both traditional and irregular challenges, while terrorist groups like al-Qaeda are irregular threats but are also actively seeking "catastrophic" capabilities.

The document is a strategic paper covering the Pentagon's Quadrennial Defense Review. In its 2000 edition it branded North Korea as a "rogue state" along with Iraq, Iran, Libya and Syria.