UK police will be able to force US-based social media platforms to hand over users' messages, including those that are "end to end encrypted," under a treaty that is set to be signed next month.

According to a report in The Times, investigations into certain serious criminal offenses, including pedophilia and terrorism, will be covered under the agreement between the two countries. Facebook's CEO Mark Zuckerberg made a large splash in March when he committed to encryption for Facebook's key messaging services, including WhatsApp, Instagram and Facebook Messenger.

The UK government has been skeptical of Facebook's encryption plans, imploring the firm to create "back doors" which would enable intelligence agencies to gain access to messaging platforms for matters of national security. Under the planned treaty, neither the US or UK would investigate the other country's citizens.

The news of the agreement between the US and UK is sure to ramp up discussion of the effectiveness of "end to end encryption" when implemented by large corporations. Facebook is currently being investigated by numerous nations and states for privacy violations, which may make it difficult to ensure that encryption equals true data privacy and censorship resistance.