The Duke of Sussex is teaming up with Oprah Winfrey for a documentary series on mental health, Kensington Palace has announced.

Prince Harry said he hoped it would show examples of “human spirit fighting back from the darkest places”. He added that he was “incredibly proud to be working alongside Oprah on this vital series, which we have been developing together for several months”.

Kensington Palace said the series would build on Harry’s long-standing work on mental health that has seen him share his personal experience and advocating for those who “silently suffer”.

Harry, 34, has championed mental health issues since revealing the “quite serious effect” his mother’s death has had on his life, admitting at times it was “total chaos” and that he had “probably been very close to a complete breakdown on numerous occasions”.

In the 2017 podcast Mad World, by the Telegraph’s Bryony Gordon, he admitted it had led him to “shutting down all of my emotions for the last 20 years” and he had only truly addressed his grief at the age of 28 after feeling “on the verge of punching someone”. He had since seen a therapist “more than a couple of times” and had reached a “good place” but hoped by speaking out to encourage others to do the same he would help break the stigma surrounding mental health.

Harry and Winfrey will be co-creators and executive producers of the series to be broadcast on the US streaming service Apple TV+.

Oprah Winfrey speaks during an event to mark the launch of Apple TV+ in March. Photograph: Michael Short/Getty Images

Winfrey told CBS This Morning that the idea came out of a conversation she had with Harry when she asked him what he thought were the most important issues facing the world. “And he said: ‘There are two: climate change, and mental wellness, mental fitness’,” she said.

Winfrey, who is one of the stars announced by Apple TV+ at its unveiling last month, told him highlighting mental health awareness was a “big concern” of hers. Harry asked her what he could to to help, and the idea was born.

“We’ve had several meetings. We’ve had secret meetings in London. I’ve flown there with the crew, sitting in sessions talking about the directions we’re going to take. Our hope is that it will have an impact on reducing the stigma and allowing people to know they are not alone,” she told the US network.

Harry, who together with Meghan, Duchess of Sussex, invited Winfrey to their wedding, said: “I truly believe that good mental health – mental fitness – is the key to powerful leadership, productive communities and a purpose-driven self.

“It is a huge responsibility to get this right as we bring you the facts, the science and the awareness of a subject that is so relevant during these times.

“Our hope is that this series will be positive, enlightening and inclusive – sharing global stories of unparalleled human spirit fighting back from the darkest places, and the opportunity for us to understand ourselves and those around us better.”

Together with the Duke and Duchess of Cambridge, Harry launched Heads Together, a mental health initiative by the Royal Foundation, and has worked with veterans around the world with the Invictus Games foundation and the Endeavour Fund as well as UK military charities to ensure the best possible mental health services for armed service personnel.

Apple TV+ , unveiled last month, is set to launch in the autumn and will compete with Netflix and Amazon Prime Video. There are as yet no details on how much the service will cost and what will be available for British viewers.