United have been pursuing De Jong all summer but despite agreeing an €85 million (£71.7m) deal with Barcelona, the midfielder has not yet left Barcelona.
Chelsea, meanwhile, are also in talks with Barcelona about a deal for the Netherlands international.
De Jong has made it clear that his preference is to remain at Barcelona, who still owe him around €17m (£14m) after he agreed to defer part of his salary to help the club’s financial situation.
But Redknapp claims he has it on good authority that De Jong is keen to make the move to Stamford Bridge before the window closes.
‘Man United are not going to get him. I’ve had that from somebody right at the very, very, very top at Man United, he’s made up [his mind], he really wants to go to Chelsea.
‘So if he goes to Chelsea, and Man United don’t get him, I don’t know where they’re going and if Chelsea get him obviously he’ll be a fantastic signing for them.’
Despite Barca’s desire to sell De Jong, Xavi insisted last month that the midfielder remains a key part of his plans.
‘I have chatted with him, he knows how much I value him, I value him very much as a footballer,’ said Xavi.
‘We have had very important private conversations that I will not reveal here. For me, he is a fundamental player for the team’s play.’
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