A North Korean defector who witnessed her first public execution aged just seven is convinced despot Kim Jong-Un would launch nuclear weapons against its enemies as a 'last stand'.

Hyeonseo Lee, who escaped in a daring mission through China, says the despotic leader would 'certainly' launch his deadly arsenal if he faced defeat at the hands of the US.

'At the very last minute, when he finds out that he's going to lose all his power he's definitely going to use it,' she told MailOnline in a fascinating interview highlighting what life is really like inside the secretive state.

'There's a slogan in North Korea which goes: 'America dies, we die, we all die together'.

'He would launch missiles at South Korea, Japan and America. He's a dictator who'd have nowhere to go and there would be no way to stop him.

Hyeonseo, now 37, went on to reveal how most North Koreans are 'brainwashed' into believing the regime's propaganda and how the thousands who are forced to attend military parades 'pee their pants' because they are forbidden from leaving.

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Embracing the West: Hyeonseo Lee, now 37, escaped North Korea as a teenager in an astonishingly daring mission through China. She says the despotic leader would 'certainly' launch his deadly arsenal as a last stand if he faced defeat at the hands of the US

Behind the curtain: Hyeonseo Lee cuddles into her mother in a picture taken inside North Korea when she was just a toddler. It is the only image that exists from her childhood inside the world's most secretive state

Freedom is not free: Hyeonseo Lee has written movingly about how her mother, pictured above with her aunt, found it difficult to adapt to life outside North Korea because of the mental imprisonment the communist regime inflicts on its people

North Korea has defied UN sanctions by threatening to launch nuclear missile tests 'weekly' and warned President Donald Trump it will 'annihilate' America if it provokes them.

And this weekend Kim Jong-un paraded new ballistic rockets, tanks and his never before seen Special Forces units through the streets of Pyongyang in a show of strength against Trump, who has refused to rule out a preemptive strike should Kim reach for the nuclear button.

It is so tiring [watching the parades] that it weakens your bones and joints... you can't even watch it at home, you have to go and watch it in person if you're living in Pyongyang. Even if you want to go to the toilet you can't, so we had to pee in our pants Hyeonseo Lee

From the safety of her new home in the South Korean capital of Seoul, where she has lived for eight years, Hyeonseo says her former compatriots are tricked into believing Kim commands the most powerful military force on earth.

'The weapons they paraded this time were all new,' she said.

'Kim wanted the world to see they have more powerful bombs and rockets than ever before and he wanted to showing America they have they're ready to fight them.

'Most people in the country didn't - and might still not - know about how powerful the United States is. They think North Korean weapons are the best in the world and they're very proud of them. They believe they can protect the country from anyone.'

She also revealed how the thousands who lined the streets and frantically waved flags at the annual Day Of The Sun parade are secretly 'sick and tired' of being forced to attend such events.

Agony: Hyeonseo Lee told MailOnline she has no doubt that the deranged dictator Kim Jong-un will use weapons. 'At the very last minute, when he finds out that he's going to lose all his power he's definitely going to use it. There's a slogan in North Korea which goes: 'America dies, we die, we all die together'.

Escape from hell: Years after escaping through China by pretending to be Chinese and passing stringent tests on its history and culture, Hyeonseo helped her mother and brother to escape in an extraordinary feat of bravery

New home: Hyeonseo brought her mother through China by pretending they were deaf and dumb to fool border guards. Astonishingly she succeeded only to face huge hurdles when she got them to Laos, pictured above, where they were detained by local police

Public execution: Hyeonseo has described being forced to watch a public execution aged just seven when a man was being strangled. What frightened me the most was the huge crowd. I was too young to really know what was going on but I was scared'. Pictured: North Korean special forces soldiers march and shout slogans during a military parade marking the 105th birth anniversary of country's founding father, Kim Il Sung last week

'It's all for praising the supreme leader [Kim], not about unity,' she said. 'People who didn't have money to spend on food and travel had to practice for countless hours just to wave flags and clap.

'The people in the crowd are sick of it [taking part in the parade]. They are still proud of the army but they don't want to take part in these events.

Bestseller: Hyeonseo Lee's account of her experience has been read all over the world

'It is so tiring that it weakens your bones and joints... and you can't even watch it at home, you have to go and watch it in person if you're living in Pyongyang.

'Even if you want to go to the toilet you can't, so we had to pee in our pants.'

Hyeonseo openly regards her country of birth as 'the most horrible on earth' but she once thought it was the greatest, as many of her former compatriots still do.

The prominent defector, who has written a bestselling book about her extraordinary lifestory, even continued to believe her life was normal long after her school cancelled classes and forced students to watch a public execution when she was seven-years-old.

'It was the first time in my life I saw a public execution,' she said. 'These days they are killing people by shooting... the hangings were scarier because they were closer to the crowds.

'What frightened me the most was the huge crowd. I was too young to really know what was going on but I was scared that a man was dying in front of me, being strangled under the bridge.

'There's a rule that the victim's immediate family and relatives have to stand at the very front to see their family member dying in front of them.'

New life: From the safety of her new home in the South Korean capital of Seoul, where she has lived for eight years, Hyeonseo says her former compatriots are tricked into believing Kim commands the most powerful military force on earth

Safe at last: 'I'd see dead bodies on the street by day and nights were a black hole,' she said of her young life in North Korea. 'We always had power shortages in the country.' Pictured: Hyeonseo above with her mother

Journey of desperation: In 1997, aged just 17, Hyeonseo trekked alone across the frozen Yalu River into China where she lived with distant relatives as an illegal immigrant for ten years before entering South Korea as refugee

Ten times a year, she and her fellow pupils were pulled from their lessons and forced to stand in total silence among a crowd of thousands to watch someone killed for crimes they were too young to understand.

But it was not until the famine of 1995 when a 15-year-old Hyeonseo saw dead, emaciated bodies strewn across the streets of her home city of Hyesan, in Ryanggang Province, that she knew North Koreans were being lied to.

I'd see dead bodies on the street by day and nights were a black hole. We always had power shortages in the country Hyeonseo Lee

'I'd see dead bodies on the street by day and nights were a black hole,' she explained. 'We always had power shortages in the country.

'I was living right next to the border with China and it was the only country I could compare to my own.

'When I looked across the river it was a completely different world - there were no people dying. It looked like a place full of colour and that's what confused me.'

In 1997, aged just 17, she trekked alone across the frozen Yalu River into China where she lived with distant relatives as an illegal immigrant for ten years before entering South Korea as refugee.

Once settled and enrolled on a degree course, she risked being executed by venturing back into North Korea to rescue her mother, who now lives with her in Seoul, and brother who is studying at Columbia University in New York.

So brave: Hyeonseo risked being executed by venturing back into North Korea to rescue her mother, who lives with her in Seoul, and brother who is studying at Columbia University in New York

Rescue: Once settled and enrolled on a degree course, she traveled back across the Yalu river, above, into North Korea to rescue her mother and brother

Hope: Hyeonseo realised something was very wrong when she looked across the Yalu river into China and saw a marked difference in the way people lived. She told MailOnline: 'It was a completely different world - there were no people dying. It looked like a place full of colour and that's what confused me'

Escape: After smuggling her family into China, Hyeonseo led them on a grueling 2,000-mile journey to Laos, Vietnam

So close: Hyeonseo's mother and brother were heading for the capital Vientiane when they were stopped by the police and imprisoned. Pictured: A guard post in China, across the Yalu river

Kindness: Unable to afford the bribes to get them out, she was out of options until she was approached by and Australian man named Dick Stolp, above with Hyeonseo, who paid for their release. Pictured: North Korean women work in front of a building in Hyesan

What weapons does Kim Jong-un have? Much has been made of whether Kim Jong-un has the nuclear capability to launch a nuclear strike against his enemies but the secretive and propagandist nature of his country make it difficult to be sure. The Institute for Science and International Security believed the secretive has as many as 21 weapons of mass destruction and four warheads. It estimated each of these weapons would have around half the power of the bomb the United States dropped on Japan in the Second World War. During the Day Of The Sun military parade over the weekend, Kim rolled out a vast array of 'new weapons' as a show of force against the United States. They included: KN-08 intercontinental ballistic missiles which can fly as far as 7,000 miles, within range of Los Angeles and New York

New solid-fuel missiles which can be fired from land or under the sea. South Korea is particularly concerned about these rockets because they are difficult to detect

Pukguksong missiles, which can be fired from a submarine and have a range of around 310 miles

The Pukguksong-2, a land-based variant of the submarine-launched missile. Also known as the KN-15 Advertisement

In 2009, she went back to north Korea to smuggle her mother and brother, her only remaining family members, into China.

She led them on a grueling 2,000-mile journey to Laos, Vietnam, because China, historically one of North Korea's fiercest allies, does not accept its citizens as refugees.

She fooled Chinese authorities by pretending her mother and brother were deaf and dumb but as they neared Vietnam's capital Vientiane, her family was arrested and imprisoned.

Unable to afford the bribes to get them out, she was on the brink of tears in a backpacker cafe when she was approached by and Australian man named Dick Stolp.

Stolp, who Hyeonseo is still close friends with today, withdrew a stack of dollars from an ATM and paid corrupt officials to free her family.

Looking back on her life and miraculous escape from oppression Hyeonseo, who wrote of her life in the book, The Girl With Seven Names, says she is embarrassed by her home country.

'The dictator is embarrassing,' she said. 'The way the regime addresses and mocks the international community is embarrassing.

Deprived: Looking back on her life and miraculous escape from oppression, Hyeonseo says she is embarrassed of her home country. Pictured: A North Korean woman carries water she collected from the Yalu river

'When I lived there... the regime told us all the time, through the media, that the international community are the enemies: United States, South Korea, Japan.

'If they heard the truth from their friends or relatives or defectors like me, they would have to keep it to themselves.

'They can't spread it to other people because Kim has too much power and he'd punish them with executions - which are becoming even more severe than in the past - and with labour camps.'