The Italian took exception to Moyes picking up the ball in injury time of City's 2-0 defeat, an action Mancini interpreted as time-wasting, and the pair had to be separated by fourth official Howard Webb before Walton's intervention.
Both were sent to the dressing rooms and, having considered referee Peter Walton's report, the FA have decided to charge Mancini.
The FA have written to Moyes to remind him of his responsibilities and conduct but he will not be charged.
Source: PA
Source: PA