The Spurs manager, favourite to be the next England boss, also claimed Fabio Capello's successor should not be named this season.
"It will be difficult for them to choose another manager if he is already working," he said.
"It will be difficult for a manager to leave a club. It is difficult when a manager says they'll quit at the end of the season - the form usually drops. You could find someone out of work - you could give it to them - but you can't give it to someone who is working at a club because that would be unfair to the club he is at."