President Donald Trump ramped up his attacks on Silicon Valley giants on Thursday with a call for "regulatory and legislative solutions" to what he described as unfair treatment of conservatives by major online platforms.
At a White House social media "summit," Trump excluded internet firms from the gathering of conservative activists who have been curbed on social media.
But he said he would invite those companies in the coming weeks for "a big meeting and a real conversation" on the topic.
Speaking to his supporters, Trump repeated his argument of political bias, claiming some activists were blocked or limited on social platforms.
Trump, a frequent Twitter user who has more than 60 million followers on that service, nonetheless renewed his complaint over "terrible bias" on social media, and vowed a response.
He offered no specific proposal but said he was directing his administration "to explore all regulatory and legislative solutions to protect free speech and the free speech of all Americans."
The latest gathering has stoked fears that the White House may seek to eliminate the legal framework that protects online services from liability over harmful content posted by others but hosted on their platforms.
Digital rights activists and others warned that removing the protection - codified as Section 230 of a 1996 law - could undermine free speech protections and the internet ecosystem.
"The government shouldn't require - or coerce - intermediaries to remove constitutionally protected speech that the government cannot prohibit directly," said a letter signed by 27 civic and digital rights organizations and 50 academics.
The letter said such demands would violate the US Constitution's First Amendment on free expression.
"Also, imposing broad liability for user speech incentivizes services to err on the side of taking down speech, resulting in overbroad censorship - or even avoid offering speech forums altogether," it added.
Eric Goldman, head of the High Tech Law Institute at Santa Clara University, said Section 230 had made the modern internet, and user generated content, possible.
"Today's most popular social websites would never have taken off and the internet would look basically like cable," he added.
Trump has repeatedly claimed that firms such as Facebook, Google and Twitter - who were not invited to the summit - discriminate against him and his supporters, even though his own Twitter account has nearly 62 million followers.