ISTANBUL (Reuters) - Turkey's competition authority has fined Alphabet Inc's ( GOOG ) Google 2.61 billion lira ($75 million), for taking advantage of its dominant position in ad server services market, the regulator said in a statement on Friday.

The antitrust body said Google has favored its own supply-side platform (SSP) service over rivals and that move made its competitors' operations difficult.

Google must ensure within six months that competitors are not disadvantaged and provide third-party SSPs similar conditions that are applied to its own services, the regulator added.

($1 = 34.9456 liras)

(Reporting by Ezgi Erkoyun; Editing by Ece Toksabay)