Morgan, formerly a tabloid newspaper editor in Britain, was not arrested but was "interviewed under caution" on Dec. 6 by British detectives investigating the long-running phone hacking scandal.
"This was further to a full witness statement I had already freely provided," Morgan said in a statement. "I attended that interview as requested."
He has consistently denied wrongdoing.
The Metropolitan Police said a 48-year-old journalist was questioned on that date. That means the interview was recorded and could be used in future prosecutions.
A police statement said the questioning is linked to a specific inquiry into phone hacking at Mirror Group Newspapers, one of the U.K.'s biggest media groups.
Morgan, who stepped into the CNN talk show host role long held by Larry King in early 2011, edited The Daily Mirror newspaper between 1995 and 2004.
He has told a British inquiry that he was not aware of any phone hacking during his tenure at the tabloid.
Judge Brian Leveson, who led the investigation, called Morgan's denial "utterly unpersuasive."
One issue that has not been resolved deals with Morgan's confirmation that he heard a voicemail left by former Beatle Paul McCartney on the phone of his now ex-wife, Heather Mills.
Morgan's description of the message in a 2006 article for the Daily Mail led some to wonder whether he'd got it through phone hacking.
Mills has said there was no way Morgan could have obtained it honestly. Morgan has not publicly explained how he heard the message.
Britain's long-running phone hacking scandal has led to numerous arrests and the closure of Rupert Murdoch's News of the World tabloid. Former Murdoch executives Rebekah Brooks and Andy Coulson are on trial for their alleged role in phone hacking.