Chancellor Angela Merkel has urged the German soccer 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. Federation president Wolfgang Niersbach resigned 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.