A consumer watchdog has escalated its efforts to block Google from rolling out a new privacy policy that would allow the Internet search giant to harvest more information about its users.

But the Electronic Privacy Information Center is not suing Google. Instead, it filed a federal lawsuit last week against the Federal Trade Commission, the agency charged with protecting consumers’ privacy on the Web.

In an unusual end run around the FTC, the watchdog group is asking a federal judge to issue a temporary restraining order and preliminary injunction to compel federal regulators to enforce a settlement they reached with Google last year and protect consumers who will be “left without recourse if the commission fails to enforce its order.”

Google settled charges last year that it violated privacy laws by exposing Gmail users’ personal information when rolling out its now-defunct Google Buzz social-networking service. The breach prompted an angry backlash from consumers and privacy advocates who say the company disclosed personal information without their knowledge or consent.

The 20-year settlement put Google on notice that it had to build privacy protection into its products and could not misrepresent how it handles users’ information.

Last month, Google began alerting users around the globe that, beginning on March 1, it will share data it collects from users across its dozens of services. Google says that only users who are logged into Google will be affected. Google already shared what it knew about its users across most of its services, but now it will also include YouTube and Google search history.

Google says its new privacy policy does not violate the settlement it reached with the FTC...