Alphabet's (GOOGL.O) Google was hit with a 2.95-billion-euro ($3.45 billion) European Union antitrust fine on Friday for anti-competitive practices in its lucrative adtech business, a sharp sanction that riled up U.S. President Donald Trump.

The fine, the fourth penalty Google has faced in its decade-long fight with EU competition regulators, follows bubbling trade tensions between major global powers and U.S. threats of retaliation over EU scrutiny of American tech firms.