Democratic presidential candidate Massachusetts Sen. Elizabeth Warren attends the SEIU's Unions for All summit in Los Angeles, California, U.S. October 4, 2019.

Elizabeth Warren is buying ads on Facebook that falsely claim Mark Zuckerberg has endorsed President Donald Trump, in a deliberate ploy that targets Facebook's controversial decision to allow politicians to make false claims in paid advertising.

The Democratic presidential candidate's campaign sponsored the posts that started to spread across social media on Thursday.

"Breaking news: Mark Zuckerberg and Facebook just endorsed Donald Trump for re-election," the ads reads.

While the statement isn't true, Facebook's own policy exempts ads by politicians from third-party fact-checking. That includes Warren's trolling ad, which includes a disclaimer that says the content isn't true.

On Sept. 24, the company announced it would not fact check or remove content by politicians, even if it violates the company's rules. Facebook's vice president of global affairs and communications Nick Clegg wrote in an announcement of the policy that "It is not our role to intervene when politicians speak."

Facebook's policy has drawn intense scrutiny after the company said it would allow Trump's re-election campaign to run an ad with false claims about former Vice President Joe Biden and his son. The ad was rejected by CNN for making a "demonstrably false" narrative about Biden.

Warren argues that Facebook is accepting money from and helping Trump's re-election campaign, despite the lies in the campaign's advertising.

"Facebook already helped elect Donald Trump once," Warren's ad said. "Now, they're deliberately allowing a candidate to intentionally lie to the American people. It's time to hold Mark Zuckerberg accountable."

In a statement, a Facebook spokesperson said that "If Senator Warren wants to say things she knows to be untrue, we believe Facebook should not be in the position of censoring that speech."

The Massachusetts senator, who has risen toward the top of national polls in the Democratic presidential primary, has long pushed for antitrust action against major tech companies, and has said that Facebook should be broken up into smaller companies.

Last week, in leaked transcripts of a July meeting at Facebook, Zuckerberg told employees that if Warren becomes president, "then I would bet that we will have a legal challenge, and I would bet that we will win the legal challenge."

"But look, at the end of the day, if someone's going to try to threaten something that existential, you go to the mat and you fight," Zuckerberg said.

Warren responded to Zuckerberg's comments in a tweet Tuesday morning, saying companies like Facebook engage in 'anticompetitive practices.'

"What would really 'suck' is if we don't fix a corrupt system that lets giant companies like Facebook engage in illegal anticompetitive practices, stomp on consumer privacy rights, and repeatedly fumble their responsibility to protect our democracy," Warren tweeted.