North Korea warns the US will "pay dearly" if it puts Pyongyang on a terror list over the killing of its leader's half-brother, as a suspect in the murder claims he was the victim of a conspiracy.

China's foreign ministry urges the United States and North Korea to sit down with each other face-to-face and resolve their problems, as tension continues to climb on the Korean peninsula after North Korea's latest rocket test.

North Korea has brought forward the possible date of a controversial "satellite" launch to as early as Sunday, regional governments say.