President Trump on Wednesday said the government is eyeing “concrete legal steps” against social media sites that he alleges are censoring conservatives online, issuing a renewed threat against Silicon Valley as he nudged Republicans across the country to open their own investigations into the matter.

Speaking at an event at the White House, Trump blasted the tech industry for incubating a “small group of powerful technology platforms” that now have “tightened their grip over commerce and communications in America.” In doing so, he said tech giants have bent “at the urging of the radical left” to limit the reach of conservative users, including himself, even though he retains a vast audience online.

Such attacks aren’t new for Trump, who for years has charged that Facebook, Google, Twitter and other popular Web platforms limit the reach of prominent conservative users and news sites. He often has provided scant evidence for his claims, which tech companies vehemently deny.

But the president has ratcheted up his attacks in recent months, as social media companies increasingly take more active, aggressive steps to limit Trump’s most controversial tweets and posts — particularly out of concern they may seed doubts about the legitimacy of the 2020 election and in some cases carry the potential to incite violence.

The president delivered his broadside Wednesday alongside nine Republican state attorneys general, some of whom echoed Trump’s belief that technology companies exhibit political bias against conservatives. U.S. Attorney General William P. Barr later appeared to encourage the GOP leaders in attendance to take action, stressing that the federal government does not “prevent the states from using their own state laws against platforms that are engaged in defrauding or misleading users.”

“The concern we have is the large amount of anecdotal evidence that supports the idea some of these private companies may be treating certain groups differently,” Alan Wilson, the Republican attorney general of South Carolina, said in an interview after the gathering.

Wilson added that the conversation, some of which was closed to the public, focused on the “states’ role” in combating political bias of any sort — and said the work with the Trump administration is only beginning.

Top White House and administration officials launched their latest salvo against Silicon Valley on the same day that the Justice Department asked Congress to adopt a new law that would hold Facebook, Google and Twitter legally accountable for the way they moderate content on the Web. The new request from the agency came in the form of a rare legislative proposal that specifically seeks to whittle down Section 230, a decades-old provision of federal law that spares websites from being held liable for content posted by their users — and immunizes some of their own decisions about what posts, photos and videos to leave up or take down.

“For too long Section 230 has provided a shield for online platforms to operate with impunity,” Barr said earlier in a statement. “Ensuring that the internet is a safe, but also vibrant, open and competitive environment is vitally important to America.”

The proposal seeks to ensure social media companies moderate their sites and services in a clear and consistent way, perhaps opening the door for social media users and even the U.S. government to penalize tech companies for perceived political bias. But the Trump administration’s approach is unlikely to generate much traction on Capitol Hill, even though Democrats and Republicans generally agree that social media sites should be held to greater account for failing to police the Web properly. Democratic lawmakers contend the administration should focus instead on hate speech, extremism and election disinformation that spreads virally on the Internet.

The Trump administration’s moves are likely to inflame tensions between Trump and the tech industry in a heated election year. Trump has continued to ratchet up his attacks, particularly as social media sites have grown more aggressive in responding to — and in some cases removing — his most controversial comments from their sites and services. Last week, for example, Twitter took action against a pair of tweets from Trump that had sought to cast doubt on the legitimacy of the 2020 election. The company “labeled” the comments, directing users to more accurate information that shows how “voting by mail is safe and secure.”

Roughly 30 minutes after Trump sent the initial tweet — and another predicting election “mayhem” on the horizon — Trump called out Twitter itself, claiming the company deliberately surfaces and promotes “anything bad, Fake or not, about President Donald Trump.”

“So obvious what they are doing,” he continued. “Being studied now!”

After Twitter first took action against Trump — hiding his tweet about racial justice demonstrations in Minneapolis for glorifying violence — the president responded days later by signing a sweeping, controversial executive order targeting social media sites broadly. The directive tasked the Federal Communications Commission to rethink the scope of Section 230 and the instances in which its legal shield applies to tech giants, an idea the agency, which is independent from the White House, is studying. It also called on the Federal Trade Commission to probe whether the companies’ efforts to police the Web are in line with their public promises of political neutrality.

That order also directed Barr to convene his state counterparts and work together “regarding the potential enforcement of State statutes that prohibit online platforms from engaging in unfair or deceptive acts or practices.” Trump further ordered the working group to develop “model legislation” to beef up state consumer protection laws so that they can be used to penalize perceived instances of political bias.

States such as Texas in the past have suggested they could tap laws prohibiting unfair or deceptive acts and practices to hold companies accountable for the way they police content online. Aides to Ken Paxton, Texas’s Republican attorney general, have publicly and privately signaled they have explored using such authorities to probe Google. The search and advertising giant, which owns YouTube, also faces an antitrust probe by state and federal competition watchdogs. A federal case could be filed in the coming days, The Washington Post has reported.