King has been included in Fabio Capello's plans for Saturday's friendly against Slovakia and next week's 2010 World Cup qualifier against Ukraine.
However, the Spurs skipper is unable to train between matches and his long-term knee problems mean King can only play one game a week.
The Football Association insist Capello will take no risks with King's fitness, but Redknapp is unhappy with his selection.
He believes the 28-year-old would have no chance of playing at the World Cup and cannot understand why the defender has been called up by Capello.
"We only found out officially on Sunday that Ledley had got an England call-up," Redknapp told The Sun.
"But we heard a whisper last week he was in Fabio Capello's thoughts. I explained the situation regarding Ledley's knee to Stuart Pearce and told him to pass it on to Capello.
"I said if Ledley plays against Ukraine next Wednesday, there is no way he would be able to play for us the following Saturday.
"I explained that, but they have gone and picked him anyway. I can't see it myself, it's mad. It's pointless at best.
"He barely manages anything on a Friday the day before a game, that's how it has to be with him.
"Ledley is a fantastic player for us and I would never stop any player playing for their country.
"It's great for them and it's good for Spurs if we have players in the England squad, so I am sympathetic towards him. He has played really well this season.
"But people have to understand the situation and how we have to manage him. He can play Saturday and Saturday, with a bit of work on an exercise bike or a swim in between.
"He couldn't train with England, because he doesn't train with Tottenham. There would be no point in Ledley playing against Slovakia. Why would you do that?
"You couldn't throw him in to see what he can do because you could not take Ledley to the 2010 World Cup. His knee is not up to it. It'd blow up under the strain."