Bayern Munich president Uli Hoeness claims he will never consider Borussia Dortmund to be a genuine rival until they can replicate their Bundesliga form on the European stage.
Dortmund are just one win away from clinching the league title for the second successive season, holding an eight-point advantage over Bayern with three matches remaining.
However, Hoeness has taken a swipe at their rivals, saying their record in European competition lets them down and prevents them from being regarded as a top side.
"They may have hungrier players, but they don't have any world class players,'' he said. "Dortmund have played a super season, but they will only get honoured by me when they play a super season in the Bundesliga and in Europe too.
"Two years ago, they crashed out of the Europa League humiliated, and this year they did not even come third in a really easy group, but they came fourth.
"Only when they manage to harmonise these two things, and when they show that they can compete in Europe, then I will take my hat off to them.''
Hoeness was also critical of Dortmund's claims to working on limited funds. The Westphalian club narrowly avoided bankruptcy a decade ago, thanks in part to a loan from Hoeness, but the Bayern president thinks they are now playing on their previous financial problems.
"It is always the same old story - the rich Bayern here and the poor Dortmund there,'' said Hoeness on Sky television. "Now they have extended the contract of (Mario) Gotze, bought (Marco) Reus, and (Robert) Lewandowski will follow. Let's just wait and see.
"The fairytales that (chief executive) Mr Hans-Joachim Watzke is telling, with his €45 million wage bill, he can tell to anybody who doesn't have a clue about our business. We will see when their balance sheet is produced.''
Watzke, however, says he cannot understand Hoeness' criticism and has nothing but respect for the Bayern president.
"I am not telling any fairytales,'' Watzke told Bild. "Our figures are clearly transparent and Bayern's are now about three times higher. I am very surprised at how sensitively Mr Hoeness is reacting.
"Should we lose to Bayern on purpose next time only so he doesn't have to moan? I always speak highly of Bayern. They have worked hard on all of their successes and Uli Hoeness deserves a great deal of the credit for that.''