LONDON (AFP) - Jose Mourinho boasted that giant clubs needed the best managers as he took over at Manchester United on Friday.

Mourinho said he wanted to bury the past three years at Old Trafford, which saw David Moyes and then his own mentor Louis van Gaal struggle to emulate the title-studded success achieved by legendary manager Alex Ferguson.

"I feel great," Mourinho said in an interview filmed in London on Thursday and aired Friday on the club's television channel.

"It comes in the right moment in my career because Manchester United is one of these clubs where you need really to be prepared for it because it is what I used to call a giant club.

"Giant clubs must be for the best managers and I think I'm ready for it."

United officially appointed the former Chelsea, Real Madrid, Porto and Inter Milan boss on Friday after three days of contract negotiations.