Britain’s advertising watchdog group announced on Tuesday that it will ban sexist ads, such as spots that depict women as solely responsible for cleaning or ones that show men as clumsy parents.

The Advertising Standards Agency undertook what it considers the most comprehensive review of gender stereotyping anywhere in the world and found that “a tougher line is needed on ads that feature stereotypical gender roles or characteristics which can potentially cause harm, including ads which mock people for not conforming to gender stereotypes.”

The ASA will relay its findings to its sister body, the Committees of Advertising Practice—which writes the U.K. advertising codes for all types of media, from television to newspapers to online ads. The CAP will then develop new standards for ads that feature stereotypical gender roles or characteristics to be enforced by the ASA.

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“Our review shows that specific forms of gender stereotypes in ads can contribute to harm for adults and children,” Ella Smillie, the report’s lead author, said in a statement. “Such portrayals can limit how people see themselves, how others see them, and limit the life decisions they take.”

The ASA says it won’t attempt to issue a blanket ban on gender stereotypes. It won’t, for instance, prohibit ads that depict a woman cleaning or a man doing DIY tasks. But it will seek to enjoin, for example, “an ad that suggests a specific activity is inappropriate for boys because it is stereotypically associated with girls, or vice-versa.”

The effort is reminiscent of the initiative undertaken by some of the world’s biggest advertising players in June. At the Cannes Lions Festival of Creativity, an ad industry conference, Unilever and UN Women convened the inaugural session of the Unstereotype Alliance whose members—Johnson & Johnson, Procter & Gamble, Microsoft, Diageo, AT&T—vowed to try to proactively address and eliminate stereotypes in advertising worldwide. Facebook, Google, and Twitter sent representatives to the meeting, as did major ad agencies IPG and WPP, whose CEOs Michael Roth and Sir Martin Sorrell, respectively, were in attendance.

The difference between the two approaches is that ASA’s has serious teeth. In the past, the watchdog has blocked ads for over-airbrushing—a L’Oreal campaign featuring actress Julia Roberts and supermodel Christy Turlington fell victim to that standard in 2011—and for featuring models that are too thin. Last year, it deemed a Gucci ad “irresponsible” for showing a “unhealthily thin” model.

That is a fate that companies desperately want to avoid. “There is a great stigma among advertisers of having complaints over one of their ads upheld by the ASA,” Lindsey Clay, CEO of Thinkbox, the marketing body for television advertising in the U.K. told the Financial Times. “This is a big wake-up call for the advertising industry.”