The German Football Association (DFB) has rejected allegations that there was a secret slush fund used for bribes to buy votes for the 2006 World Cup.
German publication Der Spiegel claims to have documents detailing a €6.7m (£4.9m) fund that was set up using private money from the late former Adidas boss Robert Louis-Dreyfus.
In a statement, FIFA said that it would investigate the "very serious" allegations, while the DFB said that it would take legal action against Der Spiegel.
Germany won the right to host the tournament by narrowly edging out South Africa by 12 votes to 11, but the DFB insisted that no foul play was used.
Its statement read: "The DFB categorically rejects the baseless allegations by the publication that the association had paid illicit funds in relation to the 2006 World Cup.
"The association also rejects the completely unsubstantiated conclusions that these funds were used to buy votes in exchange for the World Cup."
Der Spiegel also said that 2006 World Cup organising committee president Franz Beckenbauer and German FA president Wolfgang Niersbach, who is also a UEFA and FIFA executive committee member, were aware of the slush fund by 2005. Neither has personally responded to the claim.
