North Korea has accused Washington and Seoul of fabricating the results of a probe that concluded Pyongyang sent small surveillance drones to spy on key South Korean installations in March.

In a statement this week carried by the official Korean Central News Agency, a spokesman for the North's military attacked the United States for what it said was a blindly backed confrontational conspiracy devised by the government of South Korean President Park Geun-hye, whom, not for the first time, it called a "political prostitute."

In a rare direct attack on the North Korean regime, South Korean Ministry of Defense spokesman Kim Min-seok responded, telling a press briefing: "North Korea isn't a real country is it? It doesn't have human rights or freedom. It exists solely to prop up a single person.