U.S. President Barack Obama has said he does not consider the cyber attack on Sony to be an act of war.
In an interview with cnn on Sunday, Obama said his advisers are weighing how to respond in kind to the attack.
"No, I don't think it was an act of war. I think it was an act of cyber vandalism that was very costly, very expensive. We take it very seriously. We will respond proportionately, as I said."
Obama said his government was considering putting North Korea back on a U.S. list of countries that sponsor terrorism. It was removed from the list six years ago.
On the other side, North Korea on Saturday proposed a joint investigation with the US to determine the true culprit.
