US Democratic candidate Biden calls on Facebook to change political speech rules

Democratic presidential candidate Joe Biden's campaign published an open letter to Facebook Chief Executive Mark Zuckerberg on Thursday, calling for the company to fact-check politicians' ads in the two weeks ahead of the US presidential election in November.

The letter's other demands included that Facebook promptly remove false, viral information and that there be clear rules "applied to everyone, including Donald Trump - that prohibit threatening behavior and lies about how to participate in the election."

The move adds to pressure faced by Facebook, which exempts politicians' content from its third-party fact-checking program, to alter its policies on political ads and speech.

Zuckerberg last week promised a review of its content policies after the company faced backlash over taking no action on a post by Republican President Trump that were labeled by Twitter Inc for violating the smaller rival's rules. Twitter also for the first time last month used a fact-checking label on a tweet by Trump about mail-in ballots.

The Biden campaign also emailed supporters asking them to sign a petition for Facebook to crack down on misinformation in ads. Materials on its website used the hashtag #MOVEFASTFIXIT, a play on Facebook's early "move fast and break things" motto.

In a blog post, Facebook said it would continue to protect political speech.

"We live in a democracy, where the elected officials decide the rules around campaigns," the company said.

"Two weeks ago the President of the United States issued an executive order directing Federal agencies to prevent social media sites from engaging in activities like fact-checking political statements. This week, the Democratic candidate for President started a petition calling on us to do the exact opposite," it said, referring to an executive order signed by Trump.

The Trump campaign did not immediately respond to a Reuters request for comment.