US President Donald Trump has signed an executive order he said would curb the protection for social media companies after Twitter began selective fact checks on his posts.
Under current law, companies such as Twitter and Facebook are protected over what users post.
But Mr Trump said his 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".
A White House spokesman said the president signed the order after reporters were escorted out of the Oval Office.
The move comes after Twitter this week labelled two of his posts about mail voting “potentially misleading” and provided links to news coverage of his comments.
Mr Trump responded with outrage, accusing Twitter of censorship and election interference, and threatening to possibly shut down the service.
“I’m signing an executive order to protect and uphold the free speech rights of the American people,” he said.
“Currently, social media giants like Twitter receive an unprecedented liability shield based on the theory that they’re a neutral platform, which they’re not.”
Mr Trump said he expected the order or the regulations it produced to be challenged in court.
If it was legal for him to shut down Twitter, he said, “I would do it.”
Twitter has been an essential tool for Mr Trump as a politician and as president, going back to his false claims that president Barack Obama was born in Kenya.
He has said that the social media platform allows him to avoid the press and speak directly to his 80 million followers.
Mr Trump said his order instructed the Federal Trade Commission “to prohibit social media companies from engaging in any deceptive acts or practices affecting commerce".
He said it directed the administration to ensure taxpayers' money did not go to a company that “represses free speech”.
Earlier on Thursday, Mr Trump named Twitter's head of site integrity, Yoel Roth, in a tweet complaining that the platform’s decision to fact-check his tweets could “taint” the US election.
The president has complained about Twitter’s efforts to combat manipulative and abusive content by deleting fake profiles, leading to a decline of hundreds of thousands of his followers.
The websites have denied that their actions are politically motivated, and Twitter chief executive Jack Dorsey said then he also lost about 200,000 followers in the purge.