Prince William has praised the 'extraordinary example' of an author who rebuilt his life after a stranger talked him out of jumping off a bridge.

The Duke of Cambridge penned a touching introduction to the upcoming memoir of Jonny Benjamin, who details his struggle with mental health and how he overcame a suicide attempt 10 years ago in his book The Stranger on the Bridge.

Mr Benjamin turned his life around thanks to the help of a stranger, Neil Laybourn, who talked him out of jumping off Waterloo Bridge in 2008.

Kensington Palace shared a photo of the page that William has written for the book on Twitter on Monday. The Duke looked back at how he first met Mr Benjamin and praised his 'brave journey'.

Prince William has praised the 'extraordinary example' of author Jonny Benjamin who rebuilt his life after a stranger, Neil Laybourn, talked him out of jumping off Waterloo Bridge in 2008. Pictured: The Duke and Duchess of Cambridge with Benjamin and Laybourn (far right) in 2016

Kensington Palace shared a photo of the page that William has written for the book on Twitter on Monday (pictured). The Duke looked back at how he first met Mr Benjamin and praised his 'brave journey'

The royal continued his piece by praising the mental health campaigner, author and vlogger.

William's foreword begins: 'I first met Jonny, along with Neil - the ''Stranger on the Bridge'' - in 2016 when we sat overlooking the River Thames at Waterloo.

'We talked about the desperate day that brought them both together, and Jonny's brave journey since then to raise awareness of what it is like to live with mental illness.

'As an award-winning campaigner, Jonny is passionate about tackling the stigma surrounding mental health and supporting people to have the conversation about how they are feeling, without fear or prejudice.

'Mental health is not a dirty word - we all have mental health like we do physical health, good or ill. But I have seen time and again how not seeking help when it seems too much can impact the rest of our lives.'

Benjamin (far right) details his struggle with mental health in his book The Stranger on the Bridge. The memoir will contain a contribution from Laybourn (far left) who stopped the young man from committing suicide in 2008

He continued: 'As you will read in this book, at times for Jonny it has been hard but thanks to a strong support network and his personal determination to get through, he provides an extraordinary example to us all.

'On the several occasions we have met throughout The Royal Foundation's Heads Together campaign I have been struck not only by Jonny's honesty and openness but his ability to show that a mental health diagnosis should not put limitations upon anyone.

'With Neil, I watched him run the London Marathon past that very same bridge where the journey began, and I know there is so much more on this journey to come.'

Mr Benjamin's upcoming memoir will be published on May 3

Mr Benjamin's upcoming memoir will be published on May 3, and his official website will 'chart Jonny's account of living with mental illness, from childhood to the present day.'

The memoir will contain diary entries, letters, poems, and a contribution from the man who stopped Jonny from committing suicide in 2008, on the Waterloo Bridge.

Mr Benjamin tweeted the news on his personal account, noting that he was 'so incredibly grateful and humbled by this.

'The work that the Duke is doing together with the Duchess [Kate] and Prince Harry to eradicate the stigma attached to mental health is phenomenal.

'To have the Duke's support means more than I can say!'

At the age of 20 he was diagnosed with schizoaffective disorder, a combination of schizophrenia and bipolar, and later began making films on YouTube about the condition that have since been watched by hundreds of thousands of people.

In the Queen's 2017 New Year Honours List, Mr Benjamin was awarded an MBE for his services to mental health and suicide prevention.

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