US reviews adding N Korea to state sponsor of terrorism list

President Barack Obama says the United States will consider putting North Korea back on its list of state sponsors of terrorism.

The comments came after the US rebuffed North Korea's proposal of a joint investigation into a cyber attack on Sony Pictures.

Mr Obama described the hacking incident as a very costly example of cyber vandalism but North Korea has called the allegations slander and denies any involvement.

Catharina Moh reports.