A post shared by Donald Trump has become the first to be branded 'manipulated' by Twitter.
The social media giant took action over a video appearing to show his White House rival Joe Biden endorsing the president.
The footage was shared by the U.S. leader's social media director Dan Scavino and retweeted by Trump.
It was captioned: "Sleepy Joe in St. Louis, Missouri today. 'We can only re-elect Donald Trump'."
The former Vice President actually said: "We can only re-elect Donald Trump if in fact, we get engaged in this circular firing squad here."
By the time Twitter had posted the 'manipulated content' label on it, the video had been viewed more than five million times.
The footage was the first test of a new policy the social media company began on March 5.
Twitter has vowed to highlight posts that contain manipulated or synthetic media, ranging from edited videos to more sophisticated examples known as "deep fakes" that can fabricate events that never happened.
It states: "You may not deceptively share synthetic or manipulated media that are likely to cause harm.
"In addition, we may label Tweets containing synthetic and manipulated media to help people understand their authenticity and to provide additional context."
Scavino attempted to defend the post.
He wrote: "The video was NOT manipulated. This video was simply shortened. This means every single clip on Twitter is 'Manipulated'."
