Jose Mourinho has reacted at criticism from Arsene Wenger and Jurgen Klopp over the fee for Paul Pogba.
Manchester United are thought to be closing in on a deal to sign Pogba, one which will cost a world-record fee.
Juventus have demands upwards of £100m for the player they signed from United four years ago, and the deal is now reported to be close to completion.
Last week, Arsenal manager Wenger claimed that the money involved in signing the 23-year-old was “madness”.
“It’s complete madness,” said the Frenchman, “but it seems that if you can afford to do it, you can justify it. Football has become a global competition and that is why clubs are chucking these kinds of sums around.”
Liverpool boss Jurgen Klopp questioned the fee last month, saying: “If you bring one player in for £100million or whatever, and he gets injured, then it all goes through the chimney.”
Mourinho confirmed that United would be signing a “very good midfield player” on Friday, and hinted that it would indeed be Pogba.
But the Portuguese also reacted to criticism from his fellow Premier League bosses, saying their comments were “not ethical”.
“I only speak about us,” Mourinho said. “I heard already two of my colleagues from other clubs speaking about us. I do not like that. It is not ethical.
“There are things that when I do are not ethical and when others do it everything is normal, nobody says that. I do not speak about the others. They can do what they want. Our market was good.
“We made decisions, decide to bring four players not 10, that are Manchester United level. Four that we think can really improve the squad and not just be one more. This is the profile of our market.”