BERLIN (AFP) - Uefa chief Michel Platini has failed so far to give a "credible explanation" for a US$2million (S$2.8 million) dollar payment from Fifa, the head of Germany's football league said in an interview published Thursday.

"Michel Platini needs to give an open and credible explanation to football fans on what it was about - and I stress: credible," Reinhard Rauball told the daily Sueddeutsche Zeitung.

Platini was dragged into a widening scandal at Fifa when Swiss prosecutors opened a probe last week against Fifa chief Sepp Blatter.

Part of the investigation was focused on the two million Swiss francs (S$2.9 million) Blatter paid to the French legend in 2011, apparently for consulting work done between 1998 and 2002.

Switzerland's Attorney-General Michael Lauber has said there is evidence that the payment was "disloyal" to Fifa's interests.

Platini, 60, has told AFP that he was paid the sum only a decade after the consulting work was done because of financial constraints at Fifa in 1998-2002. The state of the world body's finances for the period are unclear however.

Rauball said Platini had told Uefa members in a letter that he could not comment on the investigation - a point that the German football chief said he did not appreciate.

"As a private individual in his private, civilian sphere, he can of course do so if he feels that he needs to protect himself," said Rauball.

But given that Platini is putting himself forward as a candidate for the Fifa chief job, he needs to adhere to "higher standards".

"What Platini has revealed to us so far is simply not enough," said Rauball, himself a lawyer by training.

Fifa's worst-ever crisis began in May when US prosecutors charged 14 football officials and sports business executives over involvement in more than US$150 million of bribes.

Amid the corruption storm, Blatter announced on June 4 that he would stand down, with a special election to be held in February.

Platini had been the favourite to win that vote, but some believe his implication in the Swiss probe could harm his candidacy.