The problem of fake news on social media platforms like Facebook misinforming Americans was seriously addressed by none other than President Barack Obama Thursday.

Speaking during a joint press conference with German Chancellor Angela Merkel, he said that if people "can't discriminate between serious arguments and propaganda, then we have problems."

SEE ALSO:Did a fake news writer hand Trump the White House?

The president briefly dived into the controversy of fake news sites during the session, articulating the very real threat they pose to basic functions of democracy.

Explaining the need to protect civil liberties like free speech, Obama said this is more challenging in the digital age, when "there’s so much active misinformation, and it’s packaged very well, and it looks the same when you see it on a Facebook page or you turn on your television."

He warned that, with Americans being so misled, it's harder for the country to "know what to protect."

"We won’t know what to fight for," he said. "And we can lose so much of what we’ve gained in terms of the kind of democratic freedoms and market-based economies and prosperity that we’ve come to take for granted."

"If we are not serious about facts, and what's true and what's not, and particularly in an age of social media where so many people are getting their information in sound bites and snippets off their phones, if we can’t discriminate between serious arguments and propaganda, then we have problems," he added.

Obama: "If we are not serious about facts, and what's true and what's not... then we have problems." https://t.co/pO2n4KtSJv

— Brian Stelter (@brianstelter) November 17, 2016

For the last three months of the election, fake news outperformed real news stories on Facebook, according to a Buzzfeedinvestigation this week.The analysis found the 20 top performing fake news sites received over a million more shares, comments and reactions than the top 20 actual news sites like theNew York Times or Washington Post.

The obvious implication is that these false news stories could have unfairly swayed voters during a crucial election — a possibility CEO Mark Zuckerberg mostly dismissed days earlier.

"Only a very small amount is fake news and hoaxes. The hoaxes that do exist are not limited to one partisan view, or even to politics," he wrote in a Nov. 12 Facebook post. "Overall, this makes it extremely unlikely hoaxes changed the outcome of this election in one direction or the other."