Mancini faces a FA hearing to explain his conduct during the recent match against Everton when he tried to snatch the ball out of Moyes' hands five minutes from the end of the 2-0 defeat at Eastlands.
"I will accept the charge. I won't fight it," said Mancini.
"It is important for me to stay calm but I always want to win. Every team is under pressure in the last few games.
"We had five minutes left against Everton and I wanted to get the ball. That is all I did.
"After the game I had a drink with David Moyes. There were no problems."