Facebook and Instagram will ban President Donald Trump's account from posting for at least the remainder of his term in office and perhaps "indefinitely," Mark Zuckerberg said in a blog post on Thursday.

"We believe the risks of allowing the President to continue to use our service during this period are simply too great," the Facebook CEO wrote in the post.

"Therefore, we are extending the block we have placed on his Facebook and Instagram accounts indefinitely and for at least the next two weeks until the peaceful transition of power is complete."

The decision marks a major escalation by Facebook as it and other platforms have come under intense pressure from advocacy groups and prominent figures to ban Trump following his inflammatory rhetoric encouraging insurrection.

Facebook and Twitter took the extraordinary step on Wednesday of temporarily locking President Donald Trump's account on their platforms after his supporters stormed the Capitol building to protest the election.

If the latest restrictions hold, Facebook could be the first major platform to remove Trump permanently. Facebook's move now raises expectations for Twitter, known for being the president's preferred social media platform, to follow suit.

Twitter has confirmed that Trump deleted several tweets in order to regain his tweeting privileges sometime on Thursday, though the company declined to say when precisely he would be able to tweet again. Twitter also said that "future violations... will result in permanent suspension of the @realDonaldTrump account."

"There's this element of all the companies hand-wringing until one of them takes a step, and then in a few minutes, everyone does it," said Adam Sharp, Twitter's former head of news, government and elections.

"Nobody wants to be the first, and they just take turns on who is going to be the first one to go that time around. Then they all 'Thelma and Louise' it and make the call."

The underlying problem facing most tech platforms, he said, is that the gravity of Trump's misconduct goes far beyond the companies' efforts to build standardized systems for punishing misbehavior.

In his blog post Thursday, Zuckerberg said Facebook had determined that Trump's recent posts were "likely" intended to escalate the violence rather than the opposite. Trump has shown he "intends to use his remaining time in office to undermine the peaceful and lawful transition of power to his elected successor, Joe Biden," Zuckerberg wrote.

Facebook has already described the events surrounding Trump's posts this week as an emergency. Now, Zuckerberg has finally revealed where Facebook will draw the line for Trump — at nothing less than a deadly assault on Congress.