Washington: A defiant Twitter on Friday flagged a fresh tweet from Donald Trump for violating its rules against "glorifying violence", hours after the US president signed an executive order aimed at stripping social media giants like Twitter and Facebook of legal immunity for the content posted by third-party users.

The move came after Trump tweeted that "when the looting starts, the shooting starts" in reference to the ongoing unrest in Minneapolis following the death of George Floyd, a handcuffed African-American man who pleaded for air as a white police officer kneeled on his neck.

Twitter had earlier added fact-check links to two of Trump's tweets, enraging Trump.

"These thugs are dishonouring the memory of George Floyd, and I won't let that happen. Just spoke to Governor Tim Walz and told him that the Military is with him all the way. Any difficulty and we will assume control but, when the looting starts, the shooting starts. Thank you!" Trump tweeted.

Twitter flagged the tweet, which is now only visible if one clicks on Twitter's flag.

"This Tweet violated the Twitter rules about glorifying violence. However, Twitter has determined that it may be in the public's interest for the Tweet to remain accessible," the social media company said.

Floyd was seen pinned down in a video by a white police officer and later died.

He could be heard screaming, "I can't breathe," on the video of the incident. The video of Floyd's death has now caused outrage in the city of Minneapolis and all over the country. Residents of the city have been protesting his death since Tuesday.

According to Twitter, it generally takes action on tweets that violate its rules.

"However, we recognise that sometimes it may be in the public interest to allow people to view Tweets that would otherwise be taken down. We consider content to be in the public interest if it directly contributes to understanding or discussion of a matter of public concern," it said.

"At present, we limit exceptions to one critical type of public-interest content Tweets from elected and government officials given the significant public interest in knowing and being able to discuss their actions and statements," it said.

"As a result, in rare instances, we may choose to leave up a Tweet from an elected or government official that would otherwise be taken down," it said.

The White House later dared Twitter by re-posting Trump's tweet. Twitter also flagged the re-posted tweet.

Trump, who has more than 80 million followers on Twitter, signed an executive order on Thursday aimed at stripping social media giants of legal immunity for the content posted by third-party users after Twitter added fact-check links to two of his tweets.

The executive order calls for new regulations, under Section 230 of the Communications Decency Act, to make it that social media companies that engage in censoring or any political conduct will not be able to keep their liability shield.

Trump on Friday again accused Twitter of targeting him and his supporters as he continued his attacks on social media platforms.

"Twitter is doing nothing about all of the lies & propaganda being put out by China or the radical left Democrat Party. They have targeted Republicans, Conservatives & the President of the United States. Section 230 should be revoked by Congress. Until then, it will be regulated!," Trump tweeted after the social media giant flagged his tweet on the Minneapolis unrest.

Twitter's latest move can further escalate tensions between the president and social media platforms, the US media commented.

President Trump, who is seeking a second term in November, has already threatened to shut down social media platforms.