Facebook on Sunday dismissed as "ludicrous" suggestions it contributed to the US Capitol riot on January 6, a charge the social media giant expects will be leveled in an upcoming whistleblower interview.

Facebook's vice president of policy and global affairs Nick Clegg also vehemently pushed back at the assertion its platforms are "toxic" for teens, days after a tense recent congressional hearing in which US lawmakers grilled the company over its impact on the mental health of young users.

The world's largest social media platform has been embroiled in a firestorm brought about by an unnamed whistleblower, who has shared a trove of company documents with lawmakers and The Wall Street Journal that detail how Facebook knew its products, including Instagram, were harming girls' self-image.

The uproar was likely to continue late Sunday with the appearance of an unnamed whistleblower on news show "60 Minutes" to discuss accusations that Facebook relaxed its security safeguards after the 2020 election in a move that led it to be used by Donald Trump supporters storming the Capitol.

The New York Times reported Saturday that Clegg sought to pre-empt the whistleblower by penning a 1,500 word memo to staff alerting them of the "misleading" accusations.

Clegg pressed the case in an appearance on CNN.

"I think the assertion (that) January 6th can be explained because of social media, I just think that's ludicrous," Clegg told the broadcaster, saying it was "false comfort" to believe technology was driving America's deepening political polarization.

The responsibility for the insurrection "lies squarely with the people who inflicted the violence and those who encouraged them -- including then-president Trump" and others who asserted the election was stolen, he added.

According to the Times, Clegg in his internal memo wrote that the whistleblower will insist the problems stemmed from Facebook's 2018 decision to change its News Feed to emphasize what it calls "Meaningful Social Interactions."

While everyone "has a rogue uncle" or old classmate whose extreme views may be visible on Facebook, Clegg reportedly wrote, "changes to algorithmic ranking systems on one social media platform cannot explain wider societal polarization."

Facebook has encountered criticism that it fuels societal problems, attacks Clegg said should not rest at Facebook's feet. But he acknowledged that people with pre-existing issues may not benefit from social media use.

"I don't think it's intuitively surprising if you're not feeling great about yourself already, that then going on to social media can actually make you feel a bit worse," he told CNN.

He also disputed reporting in an explosive Wall Street Journal series that Facebook's own research warned of the harm that photo-sharing app Instagram can do to teen girls' well-being.

"It's simply not borne out by our research or anybody else's that Instagram is bad or toxic for all teens," Clegg said, but added Facebook's research will continue.