Mandaric had offered the Tottenham midfielder a £1million-a-year deal to return to Fratton Park, but the player has failed to respond and Pompey have withdrawn their offer.
"We made him what I thought was a generous offer and gave him a deadline to respond," said Mandaric.
"I made a personal effort to get this deal through and flew in early from holiday to sort it out.
"I am disappointed they didn't have the courtesy to give me a call, but perhaps it's for the best."