The world has a "responsibility" to connect the remaining two-thirds of the planet to the internet, according to Facebook CEO Mark Zuckerberg.

In a blog post on the tenth anniversary of Facebook's founding, Mr Zuckerberg said in the next decade social networks would help "answer questions and solve complex problems".

Facebook is the world's most used social network, with around 1.2 billion users.

When it launched its Initial Public Offering last year it was valued at $104bn (€77bn), one of the biggest in history.

Mr Zuckerberg hailed the last ten years as "an amazing journey so far".

He continued: "It's rare to be able to touch so many people's lives, and I try to remind myself to make the most of every day and have the biggest impact I can."

Mr Zuckerberg said giving people the power to share and stay connected was his goal.

"When I reflect on the last 10 years, one question I ask myself is: why were we the ones to build this? We were just students. We had way fewer resources than big companies. If they had focused on this problem, they could have done it.

"The only answer I can think of is: we just cared more.

"While some doubted that connecting the world was actually important, we were building. While others doubted that this would be sustainable, you were forming lasting connections."

He said he is even more excited about the next ten years than the last.

"The first ten years were about bootstrapping this network. Now we have the resources to help people across the world solve even bigger and more important problems.

"Today, only one-third of the world's population has access to the internet. In the next decade, we have the opportunity and the responsibility to connect the other two-thirds.

"Today, social networks are mostly about sharing moments. In the next decade, they'll also help you answer questions and solve complex problems."

He said over the next ten years technology would enable people to create more ways to capture and communicate new kinds of experiences.

Last week, Facebook delivered its strongest revenue growth in two years, as the internet company's mobile ad sales continued to accelerate.

It said that revenue from mobile ads represented 53% of its total advertising revenue in the last three months of the year, or $1.24bn, versus the 49% proportion that mobile ads represented in the third quarter.

Facebook said it now has 1.23 billion monthly users, with 945 millio accessing the service on a smartphone or tablet.

Overall, revenue in the fourth quarter rose to $2.585bn, compared with $1.585bn the same time the previous year.