LONDON — Britain’s competition watchdog on Friday issued a statement of objections over Google’s ad tech practices, which the regulator provisionally found are impacting competition in the U.K.

In a statement, the Competition and Markets Authority alleged that the U.S. internet search titan “has harmed competition by using its dominance in online display advertising to favour its own ad tech services.”

The “vast majority” of the U.K.’s thousands of publishers and advertisers use Google’s technology in order to bid for and sell space to display ads, the CMA said.

The regulator added that it is also “concerned that Google is actively using its dominance in this sector to preference its own services.” So-called “self-preferencing” of services by technology giants is a key concern for regulators scrutinizing these companies.

The CMA further noted that Google disadvantages ad technology competitors, preventing them from competing on a “level playing field.”

Google did not immediately respond to a CNBC request for comment.

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