“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 legitimised their violent actions.

“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 oversight board is a 20-person panel including former political leaders,human rights activists and journalists selected by Facebook to review the company’s content decisions.

The board said that,where possible,Facebook should use “less restrictive measures to address potentially harmful speech and protect the rights of others before resorting to content removal and account restriction”.

“Facebook must,within six months of this decision,reexamine the arbitrary penalty it imposed on January 7 and decide the appropriate penalty,” the board said.

“This penalty must be based on the gravity of the violation and the prospect of future harm. It must also be consistent with Facebook’s rules for severe violations which must in turn be clear,necessary,and proportionate.”

In a tweet the Republican members of the House Judiciary Committee described the decision as “pathetic” while Republican congressman Jim Jordan called for Facebook to be broken up.

Republican congressman Jim Banks said:“This is a dangerous and reckless decision and sends a clear signal to conservatives using social media - you’re not welcome here.”

On Wednesday (AEDT) Trump launched a new website designed to evade the social media bans that allows his followers to share his posts to their social media pages.