Manchester United are reportedly ready to part with around £25 million for the Croatian midfielder, who has enjoyed a brilliant season at the London club and the player did not exactly close the door on a potential move when speaking to a newspaper in his homeland.
But Redknapp said: "All of our key players are under contract. The chairman and I have discussed this and we have no intention of selling any of them.
"They are at a top club and we are looking to improve the squad in the summer, not weaken it, in order to push for a Champions League place again next season."
The retirement of Paul Scholes means United are on the lookout for a playmaker and although Modric insists he is happy at his current club, Champions League football would be on offer. "When you experience playing in Champions League, you want to keep playing in this tournament," Modric told Jutarnji List ahead of his country's match with Georgia.
"Everybody wants to know what will happen with me," he said. "I'm trying to stay calm as my national team has a really important match coming. So I will tell you the same as all ways - my club status is the same as it was before.
"But of course, if an offer comes which is good for Tottenham and for me also, then a transfer is of course possible. That doesn't mean that I'm bothered with leaving Tottenham. I'm not thinking about that every hour and every minute.
"I'm happy at White Hart Lane - my status is great, the fans like me and I do have everything I need."
Modric committed himself to the club by penning a six-year deal towards the end of last season.