Google is dropping plans to eliminate cookies from its Chrome web browser, making a sudden U-turn on four years of work to phase out a technology that helps businesses tracks users online.

The company had been working on retiring third-party cookies, which are snippets of code that log user information, as part of an effort to overhaul user privacy options on Chrome. But the proposal, also known as Privacy Sandbox, had instilled fears in the online advertising industry that any replacement technology would leave even less room for online ad rivals.

In a blog post on Monday, Google said it decided to abandon the plan after considering the impact of the changes on publishers, advertisers and “everyone involved in online advertising.”

The U.K.'s primary competition regulator, which has been involved in oversight of the Privacy Sandbox project, said Google will, instead, give users the option to block or allow third-party cookies on the browser.