The president of the German Football Association (DFB) has resigned over a Fifa payment that has resulted in a tax evasion investigation.Wolfgang Niersbach said he was taking "political responsibility" for a 6.7m euro (£4.9m) payment to Fifa.The sum was allegedly used to bribe officials of world football`s governing body to vote for Germany`s 2006 World Cup bid.Niersbach said he always worked "cleanly, confidently and correctly".On 3 November police in Frankfurt raided the headquarters of the German Football Association over allegations of tax evasion linked to the 2006 World Cup.The DFB denied the claims last month."I was involved in the bid for the 2006 World Cup from day one until the final documentation of the summer fairy tale was submitted," Niersbach said. "I would like to make it clear unmistakably once again that I had absolutely no knowledge of the background of the flow of payments that are being looked into."The homes of Niersbach, his predecessor Theo Zwanziger, and former Secretary General Horst Schmid, were also searched.In a statement, the prosecutor`s office said it had opened a probe into claims of serious tax evasion linked to the awarding of the World Cup to Germany in 2006. -BBC