FILE PHOTO: A man is silhouetted against a video screen with an Facebook logo as he poses with a laptop in this photo illustration taken in the central Bosnian town of Zenica, August 14, 2013. REUTERS/Dado Ruvic/File Photo

LONDON (Reuters) - The head of Britain's data watchdog said on Tuesday Facebook FB.O must significantly change how it does business and called for the social media giant to be subject to stricter regulation.

“Facebook needs to change, significantly change, their business model and their practices to maintain trust,” Elizabeth Denham, Information Commissioner, told members of parliament at a parliamentary committee meeting on Tuesday.

Britain’s Information Commissioner has been investigating how Facebook handled personal data after consultancy Cambridge Analytica was accused of improperly harvesting information from around 87 million users on the social network.

Denham said she had seem some improvement from the U.S.-based company but said more needed to be done and it must take greater responsibility and should be subject to more regulation.

“We have seen some evidence on the voluntary side of Facebook being more transparent, things like the provenance of political ads, but I think they need to do more and I think they should be subject to stricter regulation and oversight,” she said.