The image released by an Iranian state news agency was found to have been doctored. Photo: Khouz News
North Korea's propaganda campaign is a response to UN sanctions punishing it for a nuclear test in mid-February and further antagonised by routine US-South Korean military exercises in the weeks that followed.
George Little, a spokesman for the Pentagon, said US forces were ready to respond to "any contingency", while Japan, which has a number of bases and is also the target of Pyongyang's threats, said its government was "on full alert".
The US and South Korean militaries signed a new pact last week, providing for a joint military response to even low-level provocation by the North.
Similar ... the Iranian fighter jet at the unveiling. Photo: Mashregh News
Security experts believe the constant barrage of threats backed footage of military manoeuvres is designed to prove Mr Kim, who succeeded his late father last year, has taken a firm grip on power.
"They are upping the rhetorical ante in every possible way, but the international community is not reacting as it had hoped," said Cho Han-Bum, an analyst at the Korea Institute for National Unification, who believes a meeting of the leadership next week will further increase the exchanges.
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