Sir Alex believes it will take more than the signing of Kaka to turn Manchester City into title contenders.

Manchester United manager Sir Alex Ferguson has revealed that when it comes to winning trophies he is not concerned about Manchester City, even if they do sign Kaka.

The Sky Blues are hoping to sign the Brazilian star for a world record transfer fee of £108 million, after AC Milan accepted their offer. The player is expected to discuss the move with City officials next week.

However, the headline-making deal does not appear to faze Ferguson who told The Guardian that City remained a long way behind his rivals. He explained: “With respect, Manchester City are not where Liverpool are or where Chelsea are.”

The Scot went on to reveal that Arsenal, Chelsea and Liverpool remained the only contenders for the title and that he expected Arsenal to finish the season strongly.

“You can only worry about the teams that are taking money from your pocket or taking a trophy off you. For years, Arsenal and ourselves contested the league and all I was interested in was Arsenal, what injuries and suspensions they had – and when we played them,” he said before adding, “Now it is Liverpool and Chelsea, although Arsenal will come back – they will make a fist of it this season, no question.”

However, Sir Alex did not acknowledge that his Manchester neighbours come become a dominant force, provided they lay the right foundations. The Scot said: “It depends how many players City buy. Their thinking will be to lay down markers. It will be Robinho first and then Kaka after that and that will encourage other players to join.”

Yet the 67-year-old is clearly relishing the challenge, which he revealed was part of the job at Old Trafford. Ferguson concluded: “But the one thing about Manchester United is that it doesn’t matter what happens, you will always face a challenge.”