SAN FRANCISCO (Reuters) - Twitter Inc has used its new “manipulated media” label for the first time on a video clip of U.S. Democratic presidential candidate Joe Biden that was retweeted by President Donald Trump.

Democratic U.S. presidential candidate and former Vice President Joe Biden speaks during a campaign stop at Tougaloo College in Tougaloo, Mississippi, U.S., March 8, 2020. REUTERS/Brendan McDermid

The video, posted on Saturday by White House social media director Dan Scavino, showed Biden during a speech in Kansas City, Missouri, in which he said the words “Excuse me. We can only re-elect Donald Trump.”

Biden’s full sentence, which was cut off in the clip, was “Excuse me. We can only re-elect Donald Trump if in fact we get engaged in this circular firing squad here. It’s gotta be a positive campaign so join us.”

Twitter rolled out its new policy, which labels tweets with altered or synthetic media such as so-called deepfakes or more manually edited videos, on March 5.

The tag made its debut on Sunday afternoon, but Twitter said it failed to appear when people searched for the tweet or clicked into it, only when it was seen in timelines. A Twitter spokesman said the company was working on a fix for the glitch.

Scavino, in a subsequent tweet, said “the video was NOT manipulated” and Jenna Ellis, a senior legal adviser to the president, wrote on Twitter: “The clip was accurate and was A CLIP of Biden’s embarrassing gaffe.”

Social media companies are under pressure to police misleading or false information on their platforms ahead of the U.S. presidential election in November, in which Biden and Senator Bernie Sanders are vying to be the Democratic nominee to oust Republican President Trump.

The video, which had millions of views on Twitter, was also posted on Scavino’s Facebook page where it had about 1 million views.

The Biden campaign slammed Facebook Inc for showing the video on its platforms without labels over the weekend.

“Facebook won’t say it, but it is apparent to all who have examined their conduct and policies: they care first and foremost about money and, to that end, are willing to serve as one of the world’s most effective mediums for the spread of vile lies,” said Greg Schultz, Biden’s campaign manager.

A Facebook spokesman said on Monday the company’s third-party fact-checkers had now rated the video as “partly false.”

“We are reducing its distribution and showing warning labels with more context for people who see it, try to share it, or already have,” he said. “As we announced last year, the same applies if a politician shares the video, if it was otherwise fact checked when shared by others on Facebook.”