Borussia Dortmund sporting director Michael Zorc labelled Arsene Wenger "disrespectful" for his pursuit of Pierre-Emerick Aubameyang, telling the Arsenal manager to worry about his own players.
Wenger spoke glowingly of Aubameyang during his news conference on Thursday, praising the Gabon international's character and impressive career.
The 28-year-old has been strongly linked with a move to the Gunners as a replacement for Alexis Sanchez, who is on the verge of a move to Manchester United.
But Wenger's charm offensive has not gone down well with BVB, the Bundesliga club feeling it necessary to publicly address his words.
Speaking via Dortmund's media director, Zorc issued the following statement: "We feel it is disrespectful to speak about players from other teams. There is no contact with Arsenal.
"We assume that Arsene Wenger has enough to deal with in terms of the performances of his own players."
Tensions between Aubameyang and Dortmund's hierarchy appear to have cooled after the forward was left out of the 0-0 draw with Wolfsburg last weekend for disciplinary reasons, having missed a team meeting.
Head coach Peter Stoger has since spoken to the player and said he may be considered for selection against Hertha Berlin on Friday.
"He has not really been an issue for us this week," Stoger told a news conference.
"We had a short and good conversation on Monday, and if nothing changes, it's an issue for tomorrow [Friday].
"It's clear that it [transfer speculation] is exciting for everyone, but it was really not an issue for us. If he goes with us [to Berlin], of course he could play as well, but there is no guarantee for anyone.
"Basically, he decides whether he qualifies for this team. I currently have the impression that everything is OK.
"I plan with him moving forward and therefore we do not need to talk every day. If there was a change in the personality, I would notice, and if nothing happens in the next few hours, he's in the planning [for the game]."