WASHINGTON — Days after Facebook agreed to cooperate with Congress on its investigation of Russian meddling in the 2016 election, President Donald Trump criticized the social network for being “anti-Trump.”

Trump tweeted: “Facebook was always anti-Trump.The Networks were always anti-Trump hence,Fake News, @nytimes(apologized) & @wapo were anti-Trump. Collusion?”

Facebook said last week it would provide the contents of 3,000 ads bought by a Russian agency to congressional investigators and make political advertising on its platform more transparent. Several committees are investigating Russian interference in the 2016 election.

Facebook CEO Mark Zuckerberg responded on his Facebook page saying the social media platform tried to be neutral in the election.

“Trump says Facebook is against him. Liberals say we helped Trump,” he wrote Wednesday. “Both sides are upset about ideas and content they don’t like. That’s what running a platform for all ideas looks like.”

Zuckerberg also defended the company’s decision to cooperate with investigators. “We will do our part to defend against nation states attempting to spread misinformation and subvert elections.”