Google has begun rolling-out changes to its privacy settings to all users of its Buzz social network.

Google Buzz was criticised when it launched earlier this year, after it was revealed that the service compiled a list of users' Gmail contacts then automatically started following these people and made the list public.

Just after the service launched, Google tweaked the privacy settings to ensure this did not affect new Buzz users.

However, the search engine said that many social networkers "started using Google Buzz before we made these changes".

So in a bid to offer "everyone who uses our products transparency and control", Google Buzz will ask users to confirm who they follow and whether they want the information to be made public.

"Shortly after launching Google Buzz, we quickly realised we didn't get everything right and moved as fast as possible to improve the Buzz experience," said Google product manager, Todd Jackson, in a blog.

"You can view and edit the people you're following and the people following you, elect whether you want those lists appearing on your public Google profile, and modify any of the sites you have connected to Google Buzz, like Picasa, Google Reader, or Twitter," added Jackson.

In February, a US woman started legal action against Google Buzz, which is thought to have over 170 million users, claiming the social network violates the privacy rights of users.

See also: Google Buzz iPhone app launched