Shunsuke Nakamura's Celtic future was coming under increased scrutiny tonight after the club declined an opportunity to reject reports he has a £1 million get-out clause.

Celtic insist they are not expecting Nakamura to seek a move away from Parkhead, based on the premise he has not stated a desire to leave.

However Italian football agent Angelo Massoni has claimed four giants of world football are ready to offer Nakamura big-money contracts to prise him away from Celtic.

And Massoni believes there may be a clause in Nakamura's contract, which he signed last summer, allowing the Japanese player to leave for a fee well below his market value.

In a statement released to PA Sport, a club spokesperson said: "Celtic have a contract with Nakamura for next year and the option for a further year.

"We have been give no indication he wishes to leave the club."

Pressed on whether the clause exists, Celtic refused to offer further comment.

However there remains no bid on the table for Nakamura, and Celtic would certainly not welcome any approach.

The Scottish champions believe the Japanese playmaker is enjoying his spell in Glasgow and not looking at other options, even if Massoni — operating alongside Nakamura's agent Roberto Takuda — is trumpeting the attentions of other elite  clubs.

Nakamura was named player of the year for 2006-07 by the Scottish Professional Footballers' Association, as well as by the football writers and league sponsors, as he helped Celtic to the domestic double and the last 16 of the Champions League.

To lose him would be a major blow, with the 29-year-old established as the most creative member of the Celtic squad.

Despite the signings of Scott Brown and Massimo Donati, Nakamura is still down to fulfil the playmaker role in Celtic's midfield next season.