SEOUL- North Korea said on Saturday it was entering a "state of war" with South Korea in a continuing escalation of tough rhetoric against Seoul and Washington after coming under international sanctions for its nuclear test."From this time on, the North-South relations will be entering the state of war and all issues raised between the North and the South will be handled accordingly," a statement carried by the North's official KCNA news agency said.The two Koreas have been in a technical state of war because their 1950-53 conflict ended under an armistice and not a peace treaty.