Facebook founder Mark Zuckerberg has outlined his plans to make the social network a "privacy-focused platform."
In a blog announcing the measures, Zuckerberg said he believes social media will become more about private conversations, rather than open platforms.
That has provided a conflict for social media companies, particularly for Facebook. Messaging platforms like Messenger and WhatsApp, which are both owned by Facebook, are secure and encrypted, making it difficult to make money from targeted advertising. Facebook needs users to be active on its public platform to make use of data and sell advertising to make money, but it has come under heavy criticism over privacy issues in the past 12 months.
Last year, it emerged that political consultancy firm Cambridge Analytica had accessed the data of around 50 million users.
The Facebook founder said: "Facebook and Instagram have helped people connect with friends, communities, and interests in the digital equivalent of a town square.
"But people increasingly also want to connect privately in the digital equivalent of the living room."
He added that Facebook would not "store sensitive data in countries with weak records on human rights like privacy and freedom of expression."
"Upholding this principle may mean that our services will get blocked in some countries, or that we won't be able to enter others anytime soon. That's a tradeoff we're willing to make."
Zuckerberg did not give an exact timeline for the changes, but said the changes would be implemented over the "next few years".
"I believe we should be working towards a world where people can speak privately and live freely knowing that their information will only be seen by who they want to see it and won't all stick around forever. "
"If we can help move the world in this direction, I will be proud of the difference we've made," Mr Zuckerberg wrote.