Google has announced a plan to stop holding search records that could be linked to individuals for more than two years, in an effort to clean up its Big Brother reputation.

The internet giant had previously kept billions of search records for unspecified period — widely thought to be indefinitely — building up a massive database of private information for unclear internal purposes.

Peter Fleischer, Google’s European privacy counsel, said that the search engine giant would now “anonymise” data more than “18 to 24 months old”, with the exact date depending on international legal requirements.

When anybody searches on Google, the company retains the searcher’s internet address, the search term and the time of the search. Internet addresses used at home can easily be linked to a particular household, meaning that any breach of security could be damaging.

Last year, rival AOL published the details of 23 million searches made by 650,000 people over a three month period.

The data included searches made by a Portuguese-American in Florida, who on April 16, typed in “My cheating wife” followed by “I want to make my wife suffer,” followed quickly by “Kill my wifes mistress [sic].”

The decision was taken, said Mr Fleischer, “in response to feedback we had from the privacy stakeholder community” — code for criticism for the company’s lack of a clear data protection policy from European regulators and campaigners.

The information retained will still be available to the police if required around the world and Google believes that by holding the data for up to two years will be enough for any law enforcement requests.

“We are not aware of any obligations to hand over data older than that covered by this policy," added Mr Fleischer.

Google conducted an estimated 3.3 billion searches in the United States alone in January, according to Comscore; on a global basis that figure could easily top 10 billion in that period.

No cost on the exercise was disclosed, but Google said it represented a “major engineering effort”.