CNN has apologised for accidentally placing a black 'X' on the face of Dick Cheney during coverage of a political speech.

The AP says that the error was a "technical malfuction" and not political commentary.

The letter appeared twice on Cheney's face and is commonly used to "mark a space where one visual element is to segue into another".

CNN added that they "regret that it happened and are working...to ensure it is not repeated."