Prince Harry has said he told Twitter's CEO that the network was allowing a coup to be staged, just a day before rioters stormed the US Capitol to try to block certification of Joe Biden's election win.

The January 6 mob had been riled up by a Donald Trump speech hours earlier in which he hammered away at his false claims that the election he lost to Biden was stolen from him.

Twitter subsequently kicked Trump off the platform -- his preferred social media megaphone -- amid worries he could incite further violence after the deadly Capitol assault.

"Jack and I were emailing each other prior to January 6," Prince Harry said Tuesday at RE:WIRED, a conference hosted by technology publication Wired, referring to Twitter CEO Jack Dorsey.

"I warned him that his platform was allowing a coup to be staged. That email was sent the day before and then it happened and I haven't heard from him since," he added.

Twitter declined to comment on Harry's statements.

"The internet is being defined by hate, division and lies. That can't be right. Especially for anyone who has children," Harry went on to say during a panel discussion on misinformation.

"I would hope that as human beings, as individuals with the ability of choice and decision making, that they would worry more about... the safety of people," he added.

Harry and  his wife Meghan have pursued a life of high-profile advocacy and are now based in the United States after announcing last year they were stepping back from frontline royal duties.

They moved to Los Angeles, cutting financial ties with the royal family and signing a string of lucrative deals, including with the streaming giant Netflix, and Apple TV+.

But they caused controversy by accusing an unnamed senior member of the royal family of racism, in a tell-all interview with Oprah Winfrey that divided opinion on both sides of the Atlantic.