18/04/2017 17:03 SAST | Updated 19/04/2017 06:24 SAST

Lady Gaga And Prince William Chat About Mental Health On FaceTime

The singer opened up to the prince about suffering from post traumatic stress disorder to help "break taboos" about mental illness.

Lady Gaga makes a coffee in the luxurious kitchen of her LA home, while Prince Willliam flips open his laptop in his study at Kensington Palace.

You could almost believe it's two old friends getting together to have a chat on FaceTime.

Although the slightly stilted, almost scripted conversation that ensues shows the pair have a bigger mission in mind -- to discuss mental health as part of the The Heads Together #oktosay campaign, led by The Duke and Duchess of Cambridge and Prince Harry.

The Duke of Cambridge asked the singer to get involved after she wrote an open letter last year, revealing she had suffered from PTSD after she was sexually assaulted at 19 years old.

In their video call -- released on the Royal Family's Facebook page -- they discussed ending the stigma. Prince William said: "It's so important to break open that fear and that taboo."

"It's time that everyone speaks up," he told Lady Gaga. "Just having a conversation with a friend or family member can make such a difference."

She later tweeted:

"There's a lot of shame attached to mental illness. You feel like something is wrong with you," she said. "Even though it was hard [to talk about it] it was the best thing to come out of it."

She said once you started sharing, you found out that lots of people suffer from some kind of mental challenge."I should be so happy, but you can't help it when in the morning you wake up, you are so tired, you are so sad, you are so full of anxiety and the shakes that you can't barely think," she told 34-year-old Prince William.

The release of the video comes just days after Prince Harry revealed how he struggled to cope with the grief of losing his mother, Princess Diana.

He has talked publicly for the first time about the mental health struggles he faced following his mother's health in the hope it will help others overcome their own grief.

He revealed he sought counselling after two years of "total chaos" having spent nearly 20 years of "not thinking" about the death of Princess Diana.

Harry was 12 years old when she was killed in a car crash but he said it was not until his late 20s that he processed the grief.