Chiellini was surprisingly selected by Prandelli for Wednesday's clash at Estadio Vicente Calderon, despite missing the last three weeks because of a calf strain.
The Juventus defender was named on the bench for the side's 2-0 win at Milan last Sunday, although Juve coach Conte admitted he had no intention of fielding the centre-back.
Prandelli's move to name the 29-year-old in his squad angered Conte, who described the former Fiorentina boss as "disrespectful" for not contacting him before selecting Chiellini.
But Prandelli has been quick to respond to the criticism, insisting he is within his rights to include Chiellini.
"Our medical staff, in the last 15 days before any call, are constantly in touch with the clubs' doctors, monitoring the situation to be sure the player is ready," Prandelli said.
"To all those managers who ring me, I always said that if they deem the player ready for a league game, either in the pitch or in the bench, I have the right to call him up. I have this right.
"In this case this call has a double meaning. It's the last friendly match before a very important training camp. Chiellini told me he was available for this away game, therefore he can either play or not, but it's important to be here.
"But I repeat: when a player is on the pitch or the bench, I have the right to call him up."
Prandelli also explained his decision to omit Daniele De Rossi from the squad after the Roma midfielder punched Inter's Mauro Icardi during the 0-0 draw between the two sides last Saturday.
"I watch all the games. If they (the players) make any kind of mistake that breaks the rules, they are not called," Prandelli added.
"These players are all my sons. I called De Rossi when he wasn't playing in Roma. I hold him in the highest esteem but I don't want to go to the World Cup unprepared.
"I want a discussion now, even a spat, but after that I want everybody to be aware of what we are going to do in Brazil. I don't want such gestures."
