North Korean dictator Kim Jong-Un has no intention of starting a nuclear war, but simply fires warhead missiles when he is 'angry', his former chef has revealed.

Kenji Fujimoto, former sushi chef to Kim's father Kim Jong Il, said the leader orders firing of missiles when he gets upset about U.S. military policy and international sanctions against North Korea.

His comments comes ahead of North Korea's Workers' Party's first congress in 36 years during which Kim Jong-Un's nuclear weapons policies are expected to be formally adopted.

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Explosive temper: The former sushi chef to Kim Jong-Un's father, said the leader orders firing of missiles and nuclear warheads when he gets upset about international sanctions against North Korea

Japanese Fujimoto, who recently returned to his home country after a trip to Pyongyang, told local media that Kim Jong-Un's 'military decisions are made spontaneously'

Worryingly, Fujimoto suggested that Kim's nuclear tests are less about strategy, and more about his mood swings.

The North Korean dictator 'has no mind to start a war, Fujimoto told Japanese newspaper Mainichi Shimbun.

Fujimoto began working for Kim Jong-Il in 1982, and was his personal sushi chef for 20 years, as well as a nanny-like 'playmate' for Kim Jong-Un and his older brother Kim Jong-Chul.

He left North Korea in 2011 but has since returned several times and is often interviewed about his relationship with the secretive dictator.

Letting off steam: Kim Jong Un takes charge during a test-fire of strategic submarine ballistic missile in Pyongyang, reportedly earlier this month

Blast and bother! North Korean dictator Kim Jong-Un has no intention of starting a nuclear war, but simply fires warhead missiles when he is 'angry', according to his former chef

Yesterday, North Korea announced that its ruling Workers' Party would hold a congress from May 6,ending its silence on the date of the first such conference in36 years.

Kim Jong Un is expected to use thecongress to cement his leadership and to formally adopt hispolicy, known as 'byongjin', to push simultaneously for economicdevelopment and nuclear weapons capability.

North Korea's last party congress was in 1980, before Kimwas born. Kim, the third member of his family to lead thecountry, is believed to be 33.

Byongjin follows Kim's father's Songun, or 'military first',policy and his grandfather's Juche, the North's home-grownfounding ideology that combines Marxism and extreme nationalism.

The party congress, first announced in October, will beclosely watched for any new policies and for how the countrywill present its pursuit of nuclear-weapon capability.

North Korea's drive to develop a nuclear capability hasintensified since January, when it conducted its fourth nucleartest and followed that with a string of tests of missiles thatcould deliver such a weapon.

Old rival South Korea, and others nervously watching theNorth's defiance of U.N. resolutions aimed at curbing itsnuclear and ballistic missile technologies, expect another testwithin days.

'Considering the state of readiness at the nuclear testsite, it's our view that a nuclear test can happen at any time,' South Korean Unification Ministry spokesman Jeong Joon-hee tolda briefing on Wednesday.

South Korea's military said this week Kim's go-ahead was allthat was needed for a new test.

North Korea said this week it needed a 'powerful nucleardeterrence' to counter U.S. hostility and threats.

Jeong said South Korea expected the North's party congressto last four or five days.