North Korea has threatened to confront the United States in retaliation for White House claims that Pyongyang was behind the recent cyber attack on Sony.

In a statement, North Korea said "the army and people of the DPRK are fully ready to stand in confrontation with the US in all war spaces including cyber warfare space."

"Our toughest counteraction will be boldly taken against the White House, the Pentagon and the whole US mainland, the cesspool of terrorism, by far surpassing the 'symmetric counteraction' declared by Obama."

The North Korean statement went on to accuse US President Barack Obama of "recklessly making the rumour" that North Korea was responsible for the Sony attack, which leaked a Hollywood comedy film on the fictional assassination of North Korea's leader.

Obama said on Sunday that the United States would respond "proportionately" to the cyber-attack. "I'll wait to review what the findings are," he said in an interview to CNN, stating however, that the cyberattack was not "an act of war". He went on to say that fresh sanctions were being considered, including putting North Korea on the list of states that sponsor terrorism.

The US has sought the help of China to help curb cyberattacks by North Korea. In a foreign ministry statement China said it "opposes any country or person using infrastructure from another country to launch a cyber attack on a third-party country", but did not name North Korea.

Asked on the Sony cyberattack, China's Foreign Minister Wang Yi said, "I think to arrive at any conclusion, sufficient facts and evidence are needed. China will handle the case on the basis of facts, international laws and Chinese laws."