The Spurs chief is well aware that his star Croatian playmaker will have his 'head turned' to the possibility of plying his trade with one of those three Premier League sides as they have 'Champions League football and massive wages' on offer to him.
However, as Redknapp is plotting to break into the top-four places again next season having narrowly missed out last term, he is adamant that Modric must stay put to help the north Londoners achieve that aim. And, he claims that his chairman 'is not prepared to sell' a player of Modric's stature to one of their main rivals.
Redknapp added in the Sunday Mirror: "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.
"We need to be strengthening the squad not depleting it. In an ideal world I would hope to bring in at least three more players to give us a realistic chance of competing for a top four place in the Premier League next season.
"United, Liverpool, Manchester City, Arsenal and Chelsea, who all finished above us, are going to strengthen their squads so we have to be realistic.
"If we want to compete with them we have to be active in the transfer market, but I'm not suggesting it's going to be easy. Quality players at the right price are not easy to acquire.
"We also need to trim the squad and sell a few players."