"The Board has upheld Facebook's decision on January 7, 2021, to restrict then-President Donald Trump's access to posting content on his Facebook page and Instagram account," the FOB said in an announcement.
"Given the seriousness of the violations and the ongoing risk of violence, Facebook was justified in suspending Mr. Trump's accounts on January 6 and extending that suspension on January 7," the FOB noted, adding that it was not appropriate for Facebook to impose an "indefinite" suspension.
"It is not permissible for Facebook to keep a user off the platform for an undefined period, with no criteria for when or whether the account will be restored," it said.
The FOB required Facebook to revisit the case and then either restore Trump's account, make the ban permanent or define a suspension for a set period of time, the Xinhua news agency reported.
"The Board insists that Facebook review this matter to determine and justify a proportionate response that is consistent with the rules that are applied to other users of its platform. Facebook must complete its review of this matter within six months of the date of this decision," the FOB noted.
It also made policy recommendations for Facebook to implement in developing clear, necessary, and proportionate policies that promote public safety and respect freedom of expression.
The FOB said that it found that the two posts by Trump on January 6 severely violated Facebook's Community Standards and Instagram's Community Guidelines prohibiting praise or support of people engaged in violence.
"The Board found that, in maintaining an unfounded narrative of electoral fraud and persistent calls to action, Mr. Trump created an environment where a serious risk of violence was possible. At the time of Mr. Trump's posts, there was a clear, immediate risk of harm and his words of support for those involved in the riots legitimized their violent actions," it said in the announcement.
The FOB is a panel of about 20 former political leaders, human rights activists and journalists picked by Facebook to deliberate the company's content decisions, according to media reports.