Tottenham boss Redknapp is favourite to succeed Capello, who confirmed that he intends to stick to his pledge of leaving his post after the European Championships next summer. The FA are thought to be considering the former Portsmouth boss as the next Three Lions manager, but he is likely to face competition from Roy Hodgson and other foreign candidates for the position.
"It's very difficult for them to choose another manager if he's already working," Redknapp said. "It's difficult for a manager to agree to take over if he knows he'll be leaving his club at the end of the year. It wouldn't be fair to the club."
He added: "When managers say they'll quit at the end of the season, their form normally dips because of that. That wouldn't be an ideal situation.
"You can't do it during the season. To give it to someone who's working at a club is unfair to the club he works for."
Bookmakers have shortened the odds on Redknapp taking the job after he took Spurs on a remarkable winning streak that put them within striking distance of second-place Manchester United.
Redknapp's men have dropped just two points in their last 10 matches and a sixth straight win against Bolton on Saturday will set a new record in the Premier League era for the north London club.
Now that Spurs are practically out of the Europa League following a 2-1 loss to PAOK Salonika on Wednesday, Redknapp thinks his team have a better chance of clinching their first title for 50 years.
"The other teams up there around us will be disappointed that we've gone out," said Redknapp, whose team can move into second with a victory over Owen Coyle's side at White Hart Lane. "If I were them, I'd be saying: 'I hope they win, I hope they stay in that competition'.
"I'm sure they'll think it's a blow we're likely to get knocked out and they'd much rather see us in there every Thursday night, playing another 20-odd games or whatever it is to get to the final."
Source: PA
Source: PA