Flavio Briatore has blasted Red Bull boss Christian Horner for making critical comments about Fernando Alonso.
Amid speculation the two-time world champion might one day want to return to Formula 1, Horner recently said the Spaniard typically brings "chaos" to the teams he drives for.
"I heard Horner speak negatively about Alonso and I think that's remarkable," Briatore, who is still involved in Alonso's management, told Italy's Radio Sportiva.
"I think back to when I made sure that his team got Renault engines. I can't stand that someone like Horner talks badly about someone like Fernando.
"Fernando is not only a good driver, but also a real team player. McLaren and Honda were simply not a good match - well, that can happen," the former Renault boss added.
What Briatore does admit is that the Red Bull-Honda collaboration is working well so far.
"Red Bull gets credit for that," said the Italian. "They are not yet title candidates, but they are fast becoming that.
"However, it doesn't mean that they should talk badly about other drivers. Because if we are honest, Red Bull does not deserve a prize with regards to the proper handling of drivers."