The Data Protection Commission has expressed concern about Facebook's new smart glasses, as it is worried they could be used to covertly capture pictures and videos of other people.
Facebook last week unveiled a collaboration with Ray-Ban, called Ray-Ban Stories, that adds technology to glasses frames.
That includes the ability to capture pictures or video on built-in cameras using touch or voice controls, with the images then sent to an accompanying smartphone app.
However the DPC said it and its Italian counterpart, Garante, are concerned that the device may not give others adequate notice that they are being recorded.
"While it is accepted that many devices including smart phones can record third party individuals, it is generally the case that the camera or the phone is visible as the device by which recording is happening, thereby putting those captured in the recordings on notice," the DPC said in a statement.
"With the glasses, there is a very small indicator light that comes on when recording is occurring."
It said Facebook had not demostrated that it had properly tested the product to ensure the light was "an effective means of giving notice".
It has called on Facebook Ireland to confirm that it had done so, and called on the company to run an information campaign to explain to the public how the product could be used to capture video in a less obvious way.
Responding to the regulator, a Facebook spokesperson said:
"We know people have questions about new technologies and how they work - and it's important to us that we are part of this conversation.
"We will be working together with our regulatory partners, including the DPC as our lead regulator, to help people understand more about how this new technology works, and the controls they have."
Facebook is the latest technology company to attempt to popularise smart glasses.
Google launched its Glass product in 2013 and continues to produce a business-focused version today. Meanwhile Snapchat launched its own glasses in 2016, with its latest version offering augmented reality features to users.