Facebook said on Saturday that it had removed an ad which falsely claimed that U.S. Republican Senator Lindsey Graham supported the Green New Deal, demonstrating that it will fact-check ads from political groups but not politicians.

The ad, which ran on Friday, was put up as a stunt by a left-leaning Political Action Committee, or PAC, called The Really Online Lefty League, to test Facebook's political ad policies.

Facebook has been criticized in recent weeks over its decision to not fact-check ads run by politicians, drawing ire from Democratic candidates running in the 2020 presidential election such as former Vice President Joe Biden and Senator Elizabeth Warren.

Last week, Facebook Chief Executive Mark Zuckerberg defended Facebook's policy, saying that the company did not want to stifle political speech.

Facebook spokesman Tom Channick told Reuters on Friday that since the new ad came from a political action group, rather than a politician, it was eligible for review by the company's third-party fact-checking partners.

At the time of writing, the video could still be viewed on the PAC's Facebook page, but paid distribution had been stopped.