BRUSSELS — European governments, supported by the top justice official in the European Union, are pressing Google to halt coming changes to its privacy policies while they investigate the implications for personal data protection.

The move is a shot across the bow for a range of companies, including Facebook, that rely on the European market of 500 million people for a hefty chunk of their business. It comes amid a new drive to make privacy protection in Europe — where people are generally more wary than Americans about surveillance by companies and governments — more coherent and efficient.

Viviane Reding, the E.U. justice commissioner, called on European authorities Friday “to ensure that E.U. law is fully complied with in Google’s new privacy policy.”

She was backing a request sent Thursday by national data protection authorities to Google, asking that the search engine company suspend its plans to change its privacy policies on March 1 while they conduct an inquiry into the implications for citizens and users.