Prince Harry is sharing one of his biggest regrets.

In his new docuseries “Harry & Meghan”, the Duke of Sussex reflects on the scandal sparked when he wore a Nazi costume to a fancy dress party in 2005, when he was 20-years-old.

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“It was one of the biggest mistakes of my life,” Harry says.

Photo: JIM WATSON/AFP via Getty Images
Photo: JIM WATSON/AFP via Getty Images

“I felt so ashamed afterwards,” the royal continues.

After the incident, Harry met with Chief Rabbi Jonathan Sacks, and also met with a holocaust survivor.

“All I wanted to do was make it right. I sat down and spoke to the Chief Rabbi in London, which had a profound impact on me,” he says. “I went to Berlin and spoke to a holocaust survivor.”

Harry added, “I could have got on and ignored it and made the same mistakes over and over in my life, but I learnt from that.”

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At the time, after images of him wearing the costume were published in the press, Harry made a public apology.

“I am very sorry if I have caused any offence or embarrassment to anyone. It was a poor choice of costume and I apologize,” he said.