The Brazil international's spokesman confirmed the player met police on Tuesday (UK time) as part of a 'criminal investigation', but did not mention the nature of the inquiry.

The news comes just hours after City manager Mark Hughes said Robinho would be fined for leaving a training camp without permission last week.

West Yorkshire Police said a man was arrested and questioned on Tuesday in connection with a serious sexual assault in a Leeds nightclub on January 14.

A spokesman for the force refused to confirm the identity of the man but said he was released on bail.

Robinho's spokesman Chris Nathaniel said the player denied any wrongdoing and was happy to co-operate with police.

In a statement on the star's official website, Nathaniel said: "We can confirm that Robinho met the police today (Tuesday), as pre-arranged and as part of a criminal investigation."

"He strenuously denies any allegation of wrongdoing or criminality and is happy to co-operate with the police if required further."

Robinho, whose full name is Robson de Souza, joined City from Real Madrid in September for 32.5 million pounds ($AU 69,060,000), making him the most expensive British transfer.