Facebook this evening announced a highly anticipated video-chat function, in partnership with Skype, that means Facebook users will be able to make free video calls to Facebook friends.

The social network hosted an online launch at 7pm this evening. At the event, Zuckerberg also announced group chat and a new layout for Facebook chat.

According to Reuters, chief executive and founder Mark Zuckerberg told reporters during a visit to Facebook's Seattle office last week that the company was planning to "launch something awesome" in the next few days.

A video chat function would help Facebook retain its user base after Google announced its own social network, Google+, which hopes to rival Facebook's popularity and offers a multi-user video-chat function called Hangouts.

The video chat feature will roll out internationally over the next few weeks and, according to Facebook founder Mark Zuckerberg, is a symbol of the way social apps will become more prevalent in web users' lives. Zuckerberg also said Facebook users should expect a wave of new sharing and communication tools to be launched over the next few months.

"The next five years [will] be about the cool apps you can build, this wiring and social infrastructure... This is symbolic of the way we're going to do these things, building social apps on top of our social infrastructure … it's only possible because that social infrastructure already exists."

Key to the deal was Microsoft, which acquired Skype earlier this year for around $80m, and invested $240m in Facebook in 2007. Facebook claims it has 750 million users each month, and that an average four 4 billion items of web content are shared on the social-networking site each day.