Ferguson believes clubs need time as well as money to succeed

Manchester United manager Sir Alex Ferguson says he is not concerned about the threat posed by newly wealthy neighbours Manchester City.

City's prospective new Arab owners have set their sights on winning the Premier League title and the Champions League.

"I can't be worried," said Ferguson. "There's always challenges in football.

"Some years ago it was Chelsea, some years ago it was Arsenal. Wherever the challenges come you just have to accept it. It doesn't change anything."

The Abu Dhabi United Group funded City's stunning capture of Brazilian forward Robinho from Real Madrid for a British record fee of �32.5m on transfer deadline day.

That came after they had failed in a bid to hijack United's purchase of Tottenham striker Dimitar Berbatov.

606: DEBATE Should Ferguson be worried?

"They can talk," said Ferguson with a smile.

He added: "We have a good set-up ourselves. We have been working for years to build the team we have got."

United winger Ryan Giggs agreed with Ferguson that it takes time as well as money to build a championship-winning team.

"City have the richest owner in the world but I still see United as the biggest club in the world," said the 34-year-old.

"United have a status and history that it has taken years to build up. It stretches back to the Busby Babes, to players like Sir Bobby Charlton and George Best.

"You can't just buy a team - you need stability and a base to work from.

"But obviously major money can be a big influence because it means you can bring quality to your team."

Mark Hughes finds himself in vastly different circumstances than when he was appointed manager at Eastlands.

But Giggs backed his former Wales and United team-mate to cope with the added scrutiny.

"It will be a tough job because with the money comes pressure," he said.

"But, having worked with Mark Hughes as my manager and had him as a team-mate, I know what he is all about. It won't faze him. He is a very good manager."

Ferguson also sympathised with Hughes' situation.

"For a young manager it must be difficult," the 66-year-old Ferguson said.

"You can't judge it from when I started, it is a completely different world now. I am at the tail-end of my career. I've been through all these changes so it doesn't faze me."