US President Donald Trump has accused Facebook, YouTube and Twitter of favoring his Democratic opponents and members of his Republican party.
"But do not worry, we'll win anyway, just like we did before, so let's make America great again," Trump said on Twitter.
Facebook and Twitter declined to comment and there was no response from Google's Alavate, which owns YouTube.
Trump and other conservatives have repeatedly complained that such technology platforms unfairly treat them.
Trump has already accused Twitter of imposing restrictions on the appearance of prominent Republican members without providing any evidence, and Trump, who uses social media, has vowed to investigate Twitter's practices.
Last fall, the Department of Justice held a meeting between federal and state prosecutors to discuss allegations of repressing conservative ideas on the Internet, but concrete action has yet to be taken.