The co-founder of the website known as the "front page of the internet" has warned the world is hitting "peak social" as social networks such as Facebook and Twitter near saturation point.

Alexis Ohanian, of messaging board site Reddit, said users were increasingly turning off big social networks in favour of private messaging apps.

"I really believe that we've hit ... peak social," Mr Ohanian said. "We've reached the ceiling."

Social networking sites like Facebook have struggled to add new users in important markets like North American and Europe, although Facebook is still growing rapidly in developing markets and has around 2.3 billion monthly users.

Speaking at Business Insider's Ignition conference, Mr Ohanian named Facebook, Twitter and Instagram as all having peaked. "All of them. Social media as we know it," he said.

Mr Ohanian founded Reddit in 2005 and is now on its board. The message board site is split into forums, known as Subreddits, which Mr Ohanian said could provide a future for social media sites based around smaller groups.