“The Abu Dhabi Group controls the operations at Manchester City,” Watzke told Kicker magazine ahead of his side’s Champions League match in England on Wednesday.

Asked whether he would enter into negotiations with a sheik if asked to do so, Watzke said no. “I would not even welcome him.” 

Watzke said the Manchester City example was setting a dangerous precedent. “Possibly some other clubs would be interested if approached by rich investors. But what happens if the sheik — like he did in Malaga — pulls out. Then it becomes critical.” 

Qatari investors joined the Spanish club in 2010, but Sheik Abdullah Bin Nasser Al Thani has seemingly since lost interest and there is speculation that the club is looking for a new owner.

Europe’s controlling football body UEFA has frozen Champions League payments to the club because of overdue payables.