FILE PHOTO: A woman holds her smart phone, which displays the Google home page, in this picture illustration taken February 24, 2016. REUTERS/Eric Gaillard/Illustration/File Photo

MOUNTAIN VIEW, Calif. (Reuters) - Alphabet Inc unit Google in the coming months plans to introduce new internet browser tools to limit how users’ web activity is tracked by advertising companies and give them greater insight into why certain ads are shown to them, the company announced in blog posts on Tuesday.

“Our experience shows that people prefer ads that are personalized to their needs and interests - but only if those ads offer transparency, choice and control,” Prabhakar Raghavan, Google’s senior vice president for ads and commerce, said in one of the blog posts.

The tool would enable users of Google’s Chrome browser to delete cookies, which are virtual tracking chips that some companies use to document browsing behavior, without having to also remove cookies that enable easy log-ins to websites, Google said. It added that it also would restrict some possible methods websites may use to circumvent the new tool.

A separate add-on, which will work in multiple browsers, will list the companies involved in delivering an ad to a user, including intermediaries between the advertiser and publisher, Google said.

Google announced several other new privacy controls and policies at its annual developers’ conference on Tuesday, at a time when increased public scrutiny is forcing greater transparency in Silicon Valley.