The metaverse involves a network of virtual environments accessed via different devices where users can work, socialise and play. But while Facebook wants to be at the forefront of it, its elbowing into position has rung alarm bells in Brussels.

Margrethe Vestager told an online event organised by a group of German newspaper publishers she was concerned.

"Everything we do must be fact-based and based on the information that we can get... We need to understand it before we can decide what actions would be appropriate," said Vestager.

Facebook is already in Vestager's crosshairs over its collection and use of data. Companies can be fined up to 10 per cent of their global turnover if found guilty of breaching the bloc's antitrust rules.

Meta, which is betting the metaverse will be the successor to the mobile internet, has invested heavily in virtual and augmented reality. It has not shared many details about how brands will monetise in the metaverse.