Global Financial Market Review

Randall Stephenson, AT&T's chairman and chief executive, also told employees in a message that the company's policy chief Bob Quinn would be retiring following the disclosures of payments to lawyer Michael Cohen, who is now the focus of a series of investigations.

"There is no other way to say it - AT&T hiring Michael Cohen as a political consultant was a big mistake," Stephenson said.

"To be clear, everything we did was done according to the law and entirely legitimate. But the fact is, our past association with Cohen was a serious misjudgment. In this instance, our Washington DC team's vetting process clearly failed, and I take responsibility for that."

AT&T recently acknowledged paying some US$600,000 to Cohen, who is under scrutiny for accepting payment from companies and others seeking access to the White House, and for making a $130,000 payment to porn star Stormy Daniels, who says she had an affair with Trump about a decade ago.

"Our company has been in the headlines for all the wrong reasons these last few days and our reputation has been damaged," Stephenson said.

AT&T, which is in the middle of a contentious court battle over its deal for media-entertainment group Time Warner, acknowledged hiring Cohen's firm under a one-year contract at $50,000 per month, from January until December 2017. (AFP)