The social media giant says it made the move after a close review of recent tweets from @realDonaldTrump. Mr Trump was allowed back onto the platform having been suspended in the wake of the Capitol Hill violence.
A statement posted on Twitter’s blog said it had “made it clear” previously that the President’s account was “not above our rules”, and said it took action “in the context of horrific events” earlier this week.
The statement said: “After close review of recent tweets from the @realDonaldTrump account and the context around them — specifically how they are being received and interpreted on and off Twitter — we have permanently suspended the account due to the risk of further incitement of violence.
“In the context of horrific events this week, we made it clear on Wednesday that additional violations of the Twitter rules would potentially result in this very course of action.
“Our public interest framework exists to enable the public to hear from elected officials and world leaders directly. It is built on a principle that the people have a right to hold power to account in the open.
“However, we made it clear going back years that these accounts are not above our rules entirely and cannot use Twitter to incite violence, among other things.
“We will continue to be transparent around our policies and their enforcement.”