After seeing a ?22million bid knocked back for Modric last month, Chelsea reportedly returned with an improved offer on Monday.
Modric has repeatedly stated he wants to leave White Hart Lane to complete a "dream" move to Chelsea and the 25-year-old on Saturday accused Spurs chairman Daniel Levy of "twisting the facts" about a meeting between the two concerning his future last week.
Modric claims Levy reneged on a deal to allow him to leave this summer for a bigger club, but Spurs insist no such agreement exists and they are adamant the former Dinamo Zagreb man will not be sold at any price.
Redknapp has been scathing of Chelsea's approach for Modric, describing their opening offer for his midfield maestro as "farcical" and "a joke".
He was just as unimpressed with the latest attempt to prise Modric away from Spurs.
"I still think ?27million is a pretty poor offer in my opinion for a player of that ability," Redknapp told Sky Sports News.
"It wouldn't be anywhere near what I value him at if he was for sale, but he is not for sale."
Chelsea owner Roman Abramovich is clearly a keen admirer of Modric having authorised the original offer for the player when his team were managerless.
The Russian, who has now installed Andre Villas-Boas as manager, could back another Chelsea offer, but Redknapp insists such a move would be pointless.
"There is nowhere to go with it really. That's the end of it. The chairman has made his stance. He is not for sale and that's it," the 64-year-old added.
When asked whether a bid of ?30million may change the club's stance, Redknapp said: "I don't think so. I honestly value him way in excess of that."
Modric's representative Nikki Arthur Vuksan has confirmed the player will be going on the club's pre-season trip to South Africa.
"Of course Luka will be going to South Africa. He is a Tottenham player and he has a contract there," he said.
Source: Team Talk
Source: Team Talk