North Korean media have reported President Kim Jong-un successfully piloting and landing a plane by himself. Courtesy DPRK Video

NORTH Korea’s “Supreme Leader” Kim Jong-un has executed an army general for disagreeing with him, it has been revealed.

A South Korean official says that General Pyon In-son was killed last month for expressing an opinion that differed to Mr Kim’s, Bloomberg reports.

It is not clear what the two disagreed over.

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Kim regularly purges the upper ranks of his military to strengthen his power.

He had his own uncle and his deputy Jang Song-thaek executed in 2013 and he followed that up last year by killing as many as 50 officials for various charges, including watching South Korean soap operas.

Meanwhile, Kim has raised some eyebrows by exchanging a new year’s greeting cards with United Nations secretary-general Ban Ki-moon, who is South Korean.

“Our leader has sent a new year’s card in return for Ban Ki-moon’s new year card,” a diplomat with North Korea’s mission to the UN, Kim Song, said of the rare exchange on Thursday.

North and South Korea technically remain in a state of war, and Pyongyang strongly objects to Seoul’s joint military drills with the US.