Alphabet’s Google said on Monday it is working on a policy update to restrict its ads from being placed on fake news sites as concerns mount about the rapid spread of inaccurate information online.

The policy change is imminent, Google spokeswoman Andrea Faville told Reuters.

“Moving forward, we will restrict ad serving on pages that misrepresent, misstate, or conceal information about the publisher, the publisher’s content, or the primary purpose of the web property,” she said in a statement.

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The policy change comes amid an intensifying debate over how much responsibility technology companies bear for monitoring the accuracy of content as more and more people access news through sites such as Facebook fb rather than traditional media companies.

Facebook, in particular, has been criticized over the spread of inaccurate articles promoting U.S. president-elect Donald Trump on the site. Facebook Chief Executive Mark Zuckerberg has denied that the site influenced the outcome of the election.

Google’s goog AdSense advertising network is a key financial driver for many publishers. The company places various restrictions on where its ads may be placed, including bans on pornographic and violent content. Work on the policy update began before the election, Faville said