Google is reportedly near to agreeing a record settlement with a US regulator to resolve charges related to the alleged bypassing of Apple users' privacy settings.
According to The Wall Street Journal, the US search giant is expected to be hit with a $22.5 million (£14.4m) fine by the US Federal Trade Commission (FTC) over claims that it violated privacy settings in the Safari browser in Apple devices.
The fine would be the largest ever penalty imposed by the FTC, said the Journal's unnamed sources.
Google is understood to have used a special computer code, or "cookies", to bypass the privacy controls in Safari, Apple's web browser, in order to track users of its tech rival's computers and mobile devices.
The firm said that it no longer uses the practice.
CNET reports that the FTC was looking into whether Google may have reneged on assurances it gave in 2011 over privacy concerns related to the ill-fated Google Buzz service.
That settlement required Google to "obtain express affirmative consent" from users before it proposed any "additional sharing" of certain types of personal information.
It is understood that the outlined sanctions for breach of that agreement amount to up to $16,000 a day.
Google said in a statement that the tracking of Apple users was inadvertent and did not cause any harm to consumers.
The firm said that it had used functionality in Safari to provide features to users that had already enabled Google services.
Google also claimed that the advertising cookies generated by the practice did not gather any personal information on users.
"The FTC is focused on a 2009 help centre page. We have now changed that page and taken steps to remove the ad cookies," Google told the Journal.
An FTC spokesman declined to comment on the report.
Google is also facing a separate investigation by the FTC into whether it has used anti-competitive practices in its search business to the detriment of rivals.
The European Union is also running a similar investigation into the company, although Google has recently moved to address concerns of European regulators.