Meta founder Mark Zuckerberg has unveiled several ambitious artificial-intelligence projects, describing AI as "the key to unlocking the Metaverse".

In a livestreamed demonstration, he created a basic virtual world - including an island, trees and a beach - using the AI feature Builder Bot.

Mr Zuckerberg also announced a plan to build a universal speech translator.

"The ability to communicate with anyone in any language is a superpower that was dreamt of forever," he said.