The new measure, introduced on Friday, appears to take aim at overseas websites that, for profit or propaganda purposes, impersonate local news sites in U.S. cities. The country-of-origin rule is part of broader new guidelines against fake or misleading news:

Do not misrepresent yourself or your purpose. Sites included in Google News must not misrepresent, misstate, or conceal information about their ownership or primary purpose, or engage in coordinated activity to mislead users. This includes, but isn’t limited to, sites that misrepresent or conceal their country of origin or are directed at users in another country under false premises.

“We want to ensure that people can understand and see where their news online is coming from and that sites are being transparent about their origins,” said a Google spokesperson.

The move is significant because publishers often get big bursts of web traffic through Google News, which means it could curtail the reach of impostor sites.

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Such sites have been part of a larger effort by foreign governments, particularly Russia, to spread propaganda and misinformation through the online services of U.S. tech companies.

As Bloomberg reported, the Kremlin had considerable success building a social media following by using Twitter handles like @TodayPittsburgh and @TodayMiami.

While Twitter and Facebook have had a more prominent role in the fake news phenomenon, Google also acts as a major news distributor and the sites masquerading as U.S. outlets have appeared in Google News.

The measure does not appear to affect sites like RT.com, which is a major English-language propaganda outlet for the Kremlin, since RT does not disguise the fact it is from Russia. Nonetheless, stories from RT are likely to become less visible to Americans in light of Google’s recent decision to “de-rank” them in its search engine—a move that drew the ire of Russia.