There's a likely reason AT&T paid Donald Trump's lawyer Michael Cohen $600,000: It wanted its deal for Time Warner to pass regulatory approval.

In hindsight, AT&T didn't spend its money well. Not only is Cohen under federal investigation for his business practices, but the Trump administration's Department of Justice sued to block the $85 billion acquisition.

"There is no other way to say it — AT&T hiring Michael Cohen as a political consultant was a big mistake," the company said in a statement Friday.

AT&T hired Cohen after Trump's lawyer told the company he planned to leave the Trump Organization during "the post-election transition period," AT&T said in its memo to employees. AT&T then signed a one-year contract for $50,000 a month through 2017 for Cohen's consultancy services.

"Our contract with Cohen was expressly limited to providing consulting and advisory services, and it did not permit him to lobby on our behalf without first notifying us (which never occurred)," the company said. "We didn't ask him to set up any meeting for us with anyone in the Administration and he didn't offer to do so."