The Duchess of Sussex felt it would be ''wrong'' not to speak out in the wake of George Floyd's death.

The 38-year-old duchess - who was known as Meghan Markle before her marriage to Prince Harry - admitted she was unsure what was the ''right'' thing to say about the tragedy and subsequent anti-racism protests but realised the worst thing she could do was to hold her silence about the situation.

Referencing the deaths of people of colour at the hands of police, she said in a video message to the graduating class of her old Los Angeles school, Immaculate Heart High: ''What is happening in our country and in our state and in our hometown of LA has been absolutely devastating.

''I wasn't sure what I could say to you. I wanted to say the right thing and I was really nervous that it would get picked apart.

''I realised the only wrong thing to say is to say nothing because George Floyd's life mattered and Breonna Taylor's life mattered and Philando Castile's life mattered and Tamir Rice's life mattered... and so did so many other people whose names we know and whose names we do not know...''

Meghan - who has 12-month-old son Archie with Harry - apologised to the students for having to grow up in a world where racism is still prevalent and reflected on some advice she was given as a teenager.

She said: ''I was thinking about this moment when I was a sophomore, I was 15... it's the year we do volunteer work.

''And I remember one teachers, Ms Pollia, said to me, 'always remember to put other's needs above your own fears.'

''That has stuck with me throughout my entire life and I have thought about it more in the last week than ever before.

''So the first thing I want to say to you is that I'm sorry. I'm so sorry that you have to grow up in a world where this is still present.''

The former 'Suits' actress, who is biracial, recalled her own childhood memories of the Los Angeles riots and knows they will never fade.

She said: ''I was 11 or 12 years old and it was the LA Riots, which was also triggered by senseless act of racism.

''I remember the curfew and I remember rushing back home and on that drive home, seeing ash fall from the sky and smelling the smoke and seeing the smoke billow out of buildings.

''I remember seeing men in the back of a van just holding guns and rifles. I remember pulling up the house and seeing the tree, that had always been there, completely charred. And those memories don't go away.''

Meghan called on the students to be ''part of a movement'' of hope and to use their voices ''in a stronger way'' than ever before.

She continued: ''I know you know that Black lives matter.

''We're seeing that right now, from the sheriff in Michigan or the police chief in Virginia. We're seeing people stand in solidarity, we are seeing communities come together and to uplift. You are going to be part of this movement.

''With as diverse, vibrant and opened minded as I know the teachings are at Immaculate Heart, I know you know that Black lives matters. You're going to use your voice in a stronger way than you have ever been able to because most of you are 18 - or you're turning 18 -- so you're going to vote.

''You're going to have empathy for those who don't see the world through the same lens that you do. You're ready. We need you and you're prepared.''