Arsenal manager Arsene Wenger was annoyed after Lyon confirmed that the Gunners made an offer to sign striker Alexandre Lacazette.
The French side released a public statement to announce that they refused an offer from the North Londoners for the player because he is not for sale.
And Wenger believes that official offers should be kept as "secret as possible".
"Lyon is responsible for their own statements," Wenger said.
"On the transfer front, I think the best [option] is always to keep as secret as possible. If we sign somebody, we will announce it. But I cannot tell you much more on that."
On Tuesday, Lyon published the following statement on their official website.
"Arsenal made an offer of €35m which Lyon didn't accept for one reason alone – we will keep Alexandre Lacazette.
"Lacazette is one of the main leaders of Bruno Genesio's squad.
"We categorically deny having received an offer of €48m [£40.2m] from Arsenal for him, as has been reported."