Mark Zuckerberg, CEO of Facebook, has revealed that he had called President Barack Obama to express his frustration over reports of repeated global surveillance programs by the US government.

The head of the world's most popular social networking website has said through his post that his company is working hard on security measures to protect users against criminals, and not the US government.

Zuckerberg's outburst came a day after The Intercept reported that the National Security Agency (NSA) impersonated a Facebook server to collect datas from the computers of surveillance targets. The report is based on the documents leaked by former NSA contractor Edward Snowden, who has been granted temporary asylum in Russia.

However, the NSA has denied the claims of the leaked documents, arguing that it "uses its technical capabilities only to support lawful and appropriate foreign intelligence operations, all of which must be carried out in strict accordance with its authorities."

Some of the technology giants like Facebook, Google and Microsoft had expressed their displeasure on the NSA's mass surveillance programs in the past.

Here is the complete text of Zuckerberg's Facebook Post:

As the world becomes more complex and governments everywhere struggle, trust in the internet is more important today than ever.

The internet is our shared space. It helps us connect. It spreads opportunity. It enables us to learn. It gives us a voice. It makes us stronger and safer together.

To keep the internet strong, we need to keep it secure. That's why at Facebook we spend a lot of our energy making our services and the whole internet safer and more secure. We encrypt communications, we use secure protocols for traffic, we encourage people to use multiple factors for authentication and we go out of our way to help fix issues we find in other people's services.

The internet works because most people and companies do the same. We work together to create this secure environment and make our shared space even better for the world.

This is why I've been so confused and frustrated by the repeated reports of the behavior of the US government. When our engineers work tirelessly to improve security, we imagine we're protecting you against criminals, not our own government.

The US government should be the champion for the internet, not a threat. They need to be much more transparent about what they're doing, or otherwise people will believe the worst.

I've called President Obama to express my frustration over the damage the government is creating for all of our future. Unfortunately, it seems like it will take a very long time for true full reform.

So it's up to us -- all of us -- to build the internet we want. Together, we can build a space that is greater and a more important part of the world than anything we have today, but is also safe and secure. I'm committed to seeing this happen, and you can count on Facebook to do our part.