Former Saints boss Harry Redknapp has revealed why he quit rivals Portsmouth to join Tottenham Hotspur.

The move comes after Spurs, bottom of the Premier League, sacked coach Juande Ramos last night night.

The two clubs have agreed a compensation package of £5m.

Redknapp said: "It's a big opportunity to manage a big club before I retire.”

He added Spurs are four points adrift at the bottom of the Premier League after taking just two points from eight matches this season.

A Tottenham statement on Saturday read: "The club can announce that Damien Comolli, sporting director, Juande Ramos, head coach and first team coaches, Marcos Alvarez and Gus Poyet, have left the club, with immediate effect. We wish them well.

"Clive Allen, development squad coach, and Alex Inglethorpe, youth team manager, will take charge for Sunday's league match against Bolton.

"The club has requested permission to hold discussions with Harry Redknapp and Portsmouth FC has reluctantly agreed."

Redknapp said: "It's a great opportunity for me. It's a big club, Tottenham.

"I love Portsmouth and I loved my time there, we had some fantastic success and I'd never been happier.

"But it's a great deal for Portsmouth, £5million for me, and it's a chance for me to get on and see what I can do."

Redknapp expects to be at White Hart Lane for this afternoon's clash with Bolton and plans to address the players before the match.

And despite the despair likely to be felt by Pompey fans at his departure, the former West Ham boss insists it was best for all concerned.

"It's difficult, the funds are tight. We were talking about selling players in January," Redknapp said.

"Tottenham have come in and offered £5million, which is good for the club, and if we're all being honest it was a deal which is good for the club and a chance for me to manage a big club before I retire.

"It worked out okay for everybody."

The new Tottenham manager refused to rule out raiding his old club when the transfer window opens again on January 1.

He said: "I would not sit here and say never. It depends whether the club want to sell them.

"If they did it would be an open market and we would be in there like every other Premier League club would be for one or two of the players.

"But if they did not want to sell them, then we would not be rocking the boat.

"It would be Portsmouth's decision."

Portsmouth have expressed their disappointment at the departure of Redknapp.

In a statement on the club's website, Chief executive Peter Storrie said: "Harry is a great manager and we, of course, did not want him to leave. We tried everything we could to keep him at Portsmouth.

"However, he made it clear that although he has achieved great success here at Fratton Park, apparently Spurs is one of the only clubs he would consider leaving for.

"We have subsequently agreed a substantial compensation package with Spurs, although our overwhelming desire would have been to retain the manager."

Redknapp had two spells in charge at Pompey, either side of a stint with Saints.

Storrie added: "On his return to Fratton Park, Harry performed a near miracle in keeping us in the top flight and we have since gone on to become an established top-10 side.

"Last season we won the FA Cup for the first time in nearly 70 years and qualified for European competition for the first time.

"The last thing I wanted was to see Harry leave this club but the lure of Spurs proved too much for him to turn down."

Former Arsenal and England captain Tony Adams, Redknapp's assistant at Portsmouth, will take over for today's match with Fulham and is tipped to become the new manager.