U.S. regulators warned leading Internet firms including Google to better identify paid ads in search results, particularly as new technology such as mobile services and voice-based online services become more common.
The U.S. Federal Trade Commission said on Tuesday it had sent letters to 24 Internet search companies, including giants Google, Microsoft, and Yahoo, updating its guidance on advertising practices.
The FTC's update to its 2002 guidance on search advertising practices comes as consumers are increasingly accessing the Internet on small-screened smartphones and using specialized apps and social media services to find information online.
"In recent years, paid search results have become less distinguishable as advertising, and the FTC is urging the search industry to make sure the distinction is clear," the agency said.
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