AT&T's CEO has apologized for hiring Trump personal lawyer Michael Cohen -- paying $600,000 into his shell company during 2017 for "insights" into the nascent administration -- calling it a "big mistake."

"To be clear, everything we did was done according to the law and entirely legitimate," AT&T Inc. (NYSE: T) CEO Randall Stephenson wrote in an internal memo on Friday to employees seen by Reuters. "But the fact is our past association with Cohen was a serious misjudgment."

Nonethless, AT&T's chief lobbyist, Bob Quinn, is retiring because of his role in hiring Cohen, who reportedly approached AT&T offering his services, according to sources cited by Reuters. (See AT&T Confirms Payments to Trump Lawyer's Shell Company.)

AT&T hired Essential Consultants LLC -- the firm set up by Cohen -- for advice on issues before the new administration. By far the most prominent was AT&T's proposed $85 billion acquisition of Time Warner Inc. (NYSE: TWX), which candidate Trump had decried during the 2016 presidential campaign. The Antitrust Division of the U.S. Department of Justice is attempting to block the merger and the case is now in court. (See AT&T Likens DoJ Suit to Shaved Persian Cat.)

— Dan Jones, Mobile Editor, Light Reading