He said: "Quite simply, these men and women are prized assets which need to be continually invested in".
PRINCE Harry yesterday launched a new mission to boost Our Boys and Girls' "mental fitness".
The joint initiative between the MoD and the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry comes days after the Foundation announced a £2 million investment in a start-up company providing digital support to youngsters anxious about their mental health.
Prince William spoke at the Data Observatory at Imperial College London, praising a research project which measured the success of the royal trio's Heads Together campaign that supported this year's London Marathon.
The fifth in line to the throne appeared at the Ministry of Defence in London with Defence Secretary Sir Michael Fallon to launch a partnership between the department and the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry.
And to keep the fighting fit they needed to be mentally fit - as well as being physically.
The prince, who served in the army for 10 years, will also be teaming up with Prince William and Kate Middleton after they announced the partnership between the Ministry of Defence and the Royal Foundation, according to the Guardian.
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"She had seen that at the core of adult issues like addiction and family breakdown, unresolved childhood mental health issues were often part of the problem".
"It was Catherine who first realised that all three of us were working on mental health in our individual areas of focus".
Experts noted, the publicity arising from initiatives including the the London Marathon and Harry's interview about his own mental health had inspired more men to come forward and start a conversation about their difficulties. It is an issue richly deserving of their support, and one which everyone concerned with society's welfare should also back.
Discussing the statistic that three quarters of suicides in the United Kingdom are men, he stated: "That's still a worrying statistic though, it really is".
The Duke added: "At the beginning, we were trying to understand why at home people weren't sharing some of their problems".
He said he wanted troops to think about mental health in the same way they did about physical health.