Chancellor Angela Merkel has urged the German football federation to ascertain allegations surrounding the 2006 World Cup.
A suspect payment to FIFA in connection with the World Cup has triggered a string of questions in recent weeks, reports Xinhua.
Federation president Wolfgang Niersbach resigned on Monday, saying he was taking "political responsibility" despite not having done anything wrong.
The payment has led to a tax-evasion probe against Niersbach and two other former officials.
"I hope that the German Football Federation will transparently clear up everything that happened," said Merkel on Friday.