Facebook has rejected a request from former Vice President Joe Biden’s 2020 campaign to remove a video advertisement by President Donald Trump’s re-election campaign that highlights allegations of corruption against Biden and his son, according to a report.

CNN on Wednesday published Facebook’s response to the Biden campaign in which it explains its decision is “grounded in Facebook’s fundamental belief in free expression, respect for the democratic process, and belief that in mature democracies with a free press, political speech is already arguably the most scrutinized speech there is.”

The ad condemns Biden for previously threatening to withhold $1 billion in aid to Ukraine unless the eastern European country fired a prosecutor reportedly probing into an energy company which Biden’s son, Hunter, served as a board member. The 30-second clip, titled “Biden Corruption,” is running on several national cable networks and online. To run the ad, the president’s 2020 campaign spent $8 million, while the Republican National Committee (RNC) chipped in $2 million.

Biden campaign spokesperson TJ Ducklo responded angrily to Facebook’s decision, calling it “unacceptable” and said that the flow of “objectively false information to influence public opinion poisons the public discourse and chips away at our democracy.” He did not comment on the substance of the ad’s claims.

Last Monday, CNN announced it had rejected to run the ad, claiming the video “does not meet our advertising standards.”

“Specifically, in addition to disparaging CNN and its journalists, the ad makes assertions that have been proven demonstrably false by various news outlets, including CNN,” the network said in a statement.

Tim Murtaugh, Trump 2020 campaign’s communications director, ripped into CNN’s decision, accusing the network of “spend[ing] all day protecting Joe Biden in their programming.”

“[I]t’s not surprising that they’re shielding him from truthful advertising too, and then talking to other media outlets about it,” Murtaugh told the Daily Beast of the former vice president. “Our ad is entirely accurate and was reviewed by counsel, and CNN wouldn’t even describe to us what they found objectionable. This isn’t a cable news channel anymore, it’s a Democrat public relations firm.”