Andy Cole admits he regrets leaving Manchester United when he did because he'd have won more trophies - but enjoyed his time playing for Man City. The rivals face off in the Manchester derby on Saturday, and Cole knows exactly what it is like in each dressing room ahead of the clash.

Cole spent almost seven seasons at Old Trafford and won nine major honours, including the Treble. He joined United from Newcastle for a British transfer record fee at the time, signing for £6million with £1m-rated Keith Gillespie going the other way.

But he left in 2002 for even more money to join Blackburn Rovers and eventually ended up at Manchester City in 2005. Speaking after his retirement, Cole admitted he departed the Red Devils too early.

He said: "[Sir Alex] told me that I didn't have to go, he didn't want me to go. I could have stayed for as long as I could and I would get my games.

"In the end, he just said, 'Okay, I understand, and I know what you are like, I will let you go'. The crazy thing is that he sold me for £7million, which is more than what he paid for me – he got me for £6m.

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"So I remember that last meeting with him like it was yesterday. I really enjoyed my time, but I left far too early. That is my only regret. I could have stayed at the football club for a lot longer and, looking back, I wish I had."

Reflecting on missed opportunity, Cole added: "Just because you have won everything, that doesn't mean you don't want to win it again.

"If I was what I am now – more relaxed and calculated in what I want to do – I would have thought about it and realised I would have played games and still be involved in 20 to 25 games a season and win a hell of a lot more, but it wasn't to be."

Cole made the leap from one side of the city after a stint at Fulham, saying it was a "great honour" to play for both Manchester clubs. Speaking to the Independentbefore a derby in 2005, he said: "The fact I had played for United and had such a good time there was on my mind when I considered City's offer, I cannot lie.

"When you've been at a club for so long and you have achieved so much with that club, I mean I achieved things at United that I never believed I would, then you close it and move on and end up at their rivals then of course it crosses your mind.

"But I am a professional footballer, simple as that. I had a great time at United, but that came to an end, and now this is a new chapter.

"Personally, I consider it an honour to have played for both clubs in my career. Some Manchester United fans might not see it that way and some Manchester City fans might not see it that way but it really is an honour for me to have played for two great clubs."

Highlighting the other stars who made the unthinkable jump between rivals, Cole added: "A lot has been made about me coming here and you would think I am the only player ever to have made the switch.

"Denis Law did it, Brian Kidd did it, and a lot of people seem to forget that both Shaun Goater and Jon Macken played for United early in their careers, but because I had so much success with United and was there for the most successful period in the club's history people seem a lot more apprehensive about my move."