Facebook founder Mark Zuckerberg rejected US President Donald Trump's accusations that the site was biased against him.
The US president accused the site of colluding with Twitter and said they were pursuing a "Trump" policy.
Trump made the same charges for the New York Times and the Washington Post.
Facebook plans to submit some 3,000 political ads for investigation by congressional investigators looking into allegations of Russia's intervention in the recent US presidential election.
The site believes that these ads may have been bought by Russian parties during or after the elections.
He asked Facebook, Twitter and Google to testify before the Senate Intelligence Committee on November 1 on allegations of Russian intervention.
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In response to Trump's accusations, Zuckerberg said he "tried to give a voice to all ideas," adding that regardless of the problems with some ads, Facebook tried to provide a "platform for all people to communicate with their candidates and help millions of people vote."
He said both rival political parties objected to the content of the social networking site, and liberals in the United States accused him of facilitating Trump's victory in the presidency.
Zuckerberg, 33, promised that Facebook "continues to build a society for all people," adding that he is determined to address all countries trying to spread false information and undermine the integrity of the electoral process.
The Facebook founder's comments received welcome responses from 65,000 people within two hours of their publication on the social networking site.
The Kremlin denies any involvement in the US elections or Trump and his aides had ties with Russia.