Sitiveni Rabuka was charged in June by the anti-corruption body, FICAC, for providing a false declaration of assets, income and liabilities.
The former prime minister and coup leader has pleaded not guilty to the charges.
Mr Rabuka's party, SODELPA, says the unforeseen request from FICAC for a further round of interviews has meant he had to call short his week of meetings in Macuata.
It gave no details about what it is FICAC wanted to talk about.
