The Croatian was in stunning form last season as Spurs reached the Champions League quarter final and qualified for the Europa League after finishing 5th in the Barclays Premier League.
And Redknapp says that despite rumours that Modric may make the move to Chelsea or Manchester United, he has been told by chairman Daniel Levy that their prized asset won't be let go.
“If clubs the size of Manchester United and Chelsea are prepared to offer him Champions League football and massive wages, you would have to be very naive to think it wouldn’t turn Luka’s head,” he said.
“But I have been assured by the chairman that he is not prepared to sell him under any circumstances.
“And it’s fair to say he’s not happy about the unwanted attention and continuing speculation surrounding Luka. I have said on many occasions he is irreplaceable and it would be a massive disaster for the club if he was allowed to leave.”