The intense challenge and scrutiny facing Facebook and Twitter over the president’s false claims illustrates the platforms’ role as indispensable forums for billions of people to express opinions and share information — and the power the companies wield as a result. The social media companies largely operate under rules they set themselves, but those rules have increasingly become divisive.

Democratic lawmakers and progressive groups called on the social media platforms to suspend Trump's accounts, saying their current policies of labeling his misleading rhetoric still allows dangerously false narratives to proliferate online.

“Right now, the President's Twitter account is posting lies and misinformation at a breathtaking clip,” Rep. David Cicilline (D-R.I.) tweeted Wednesday. “It is a threat to our democracy and should be suspended until all the votes are counted.”

The uproar is putting the nation’s largest social networks in a deeply uncomfortable position that has become increasingly familiar as they struggle to prevent lies or deception on their platform from undermining the election. They are being squeezed by partisan fighting over the limits of online speech while having their delicately crafted policies against misinformation put to unprecedented tests by the world’s most powerful political leader.

Posts using the hashtags #StealTheVote and #VoterFraud garnered more than 300,000 interactions, including likes, comments and shares, on Facebook in the hours after Trump falsely declared victory, according to data from CrowdTangle, a social analytics firm owned by Facebook.

Misinformation trackers at the Election Integrity Partnership, a consortium of academics and researchers, told reporters they observed a concerted campaign to copy and paste Trump’s misleading tweets after Twitter prevented them from being shared, for instance. Some of those posts were also labeled.

Both Facebook and Twitter settled on policies ahead of the election that they saw as a middle ground — appending warning labels or fact checks to misleading posts. In Twitter's case, some of those labels also prevent the post from being liked or shared. But the flood of posts in the aftermath of the Nov. 3 vote has presented new challenges.

On Wednesday, Facebook expanded a policy to label premature claims of victory. The company said it would start labeling posts from any individual, not just the presidential candidates, that prematurely declared a victory in a state or the overall election.

That came after Trump's son, Eric Trump, and White House press secretary Kayleigh McEnany, were among the campaign allies who falsely claimed on Twitter that the president had emerged victorious in Pennsylvania with final results still outstanding. Twitter pinned labels to both tweets stating official sources had yet to call the race.

Democratic lawmakers and Silicon Valley critics said the fact that Trump and his surrogates repeatedly pushed misinformation, perhaps in deliberate violation of the companies’ policies, meant tougher action needed to be taken.

“Suspend his account, @Twitter. This is pure disinformation. Valid votes are being counted.This is America, not Russia,” Rep. Gerry Connolly (D-Va.) tweeted.

Twitter spokesperson Trenton Kennedy said the company "took quick action to limit engagement on a number of Tweets that may have needed more context or violated the Twitter rules" on Tuesday night. "Our teams remain vigilant and will continue working to protect the integrity of the election conversation on Twitter."

For months, Trump has been cultivating a false narrative that the presidential election is being corrupted before it happens. Now, with ballots cast, he is going even further — making claims that swing states are “finding” votes for Biden when in fact they are mail-in ballots that simply had yet to be counted. And social media has become a main vector for getting those deceptive messages out.

Liberal commentators, civil rights groups and other supporters of Biden began to push back on those false claims and urge patience while all of the remaining votes are counted. However, POLITICO’s review of CrowdTangle data showed those posts did not get the same traction on Facebook.

The advocacy group Free Press urged Twitter and Facebook to take down every false or misleading post on Wednesday, joining a call from other civil rights and progressive groups that have criticized Facebook in the past for how it handles misinformation and has speech.

“This is the Trump strategy. It’s to sow chaos, to stir up disinformation, and to organize over social media people to turn out and threaten, harass and, in some cases, even commit violence,” said Free Press CEO Jessica González.

But whether Facebook and Twitter take action against Trump’s social media posts doesn’t stop his message from being spread, said Alex Stamos, a former Facebook security chief who is now director of the Stanford Internet Observatory. In fact, those same claims are often reported by mainstream media outlets because they are newsworthy, he said.

Instead, social media companies should crack down on users who repeat or amplify those misleading narratives, or who create and distribute faked evidence designed to make the narratives seem real.

“Doing something to the output of one of the candidates in a democratic election is the highest-stakes, highest-risk component of these companies possibly interfering in the democratic process,” Stamos said. “It is the place where I think we have to be the most careful about setting precedents.”

Mark Scott and Cristiano Lima contributed to this report.