Prince Harry, the Duke of Sussex said he warned Twitter boss Jack Dorsey about political unrest in the United States a few days ahead of the January 6 Capitol riots.
“I warned him his platform was allowing a coup to be staged,” Prince Harry said at the RE:WIRED tech forum in the US.
“That email was sent the day before. And then it happened and I haven’t heard from him since,” the duke said.
Prince Harry, who now lives with his wife Duchess of Sussex in California, appeared at Tuesday’s session via video chat as a guest speaker. He was introduced as the co-founder of the Archewell organisation.
He was speaking at a session discussing whether social media was contributing to misinformation and online hatred.
The duke used his personal experience with online hatred and the press to reflect that social media companies were not doing enough to stop the spread of misinformation.
He said the internet was “being defined by hate, division and lies”, adding: “That can’t be right.”
Meanwhile, investigations into what happened on January 6, when a mob of President Donald Trump’s supporters stormed the Capitol building in Washington DC and disrupted the official certification of Joe Biden’s victory in the White House race, are continuing.
More than 670 people have been charged with taking part.
On Tuesday, a congressional committee investigating the riots summoned more of Mr Trump’s closest aides to give evidence.
Among the latest batch is a former White House press secretary, a senior policy adviser and personal assistants.
The inquiry is trying to find out if Mr Trump had foreknowledge of the attack.