North Korea proposes joint probe with the U.S. into Sony cyber attack - KCNA

North Korean leader Kim Jong Un attends a women's soccer match between the national team and the Wolmido team at the remodelled May Day Stadium in Pyongyang on October 28, 2014, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on October 29, 2014. REUTERS/KCNA

SEOUL (Reuters) - North Korea proposed a joint investigation with the United States on the cyber attack against Sony Pictures, calling the charge by the FBI that it was behind the attack "slander", state media said on Saturday.

An unnamed spokesman of the North's foreign ministry said there would be "grave consequences" if Washington refused to agree to the joint probe and continued to accuse the North, the official KCNA news agency reported.