Facebook founder Mark Zuckerberg has outlined a plan to let artificial intelligence (AI) software review content posted on the social network.

In a letter describing the plan, he said algorithms would eventually be able to spot terrorism, violence, bullying and even prevent suicide.

He admitted Facebook had previously made mistakes in the content it had removed from the website.

But he said it would take years for the necessary algorithms to be developed.

The announcement has been welcomed by an internet safety charity, which had previously been critical of the way the social network had handled posts depicting extreme violence.