Messi to Bayern? 'We can't afford it', jokes Mueller

"I spoke to our financial director once or twice over the past months. And I don't think there's anything we can do," a jestful Mueller said when asked about the possibility of signing Messi at a promotional event in Munich.

Messi reportedly earns an annual salary upwards of 50 million euros ($59 million), almost three times more than Bayern's highest-paid players, such as Robert Lewandowski, Manuel Neuer and Mueller.

Mueller admitted he never foresaw Messi leaving Barcelona before retiring as a player but said he understood why the prospect of the Argentine's Camp Nou exit was drawing such huge interest.

"The fact that some change is happening now might also be interesting for the footballing world," said Mueller.

"Apart from Barcelona fans, which I can understand, nobody is really able to see this departure with a critical eye. People are rather curious to know what new avenues will open up," he added.

Bayern chief executive Karl-Heinz Rummenigge told Italian sports daily Tuttosport that the German club could "not pay a player of that calibre".

"That is not part of our policy or our philosophy," he said.

Manchester City, coached by former Barcelona boss Pep Guardiola, Paris Saint-Germain and Inter Milan are the clubs most strongly linked with an audacious swoop for the six-time Ballon d'Or winner.