There is a "big chance" of Rio Ferdinand leaving Manchester United in the summer when his current contract ends, with the 34-year-old seriously considering a move from Old Trafford.

The defender has told friends he has no intention of retiring and is weighing up his future at United, who he joined from Leeds in 2002 for a then record £30m fee, with a move abroad the most likely option should he depart. One choice could be a lucrative deal to play in China, though nothing is being ruled in or out.

Sir Alex Ferguson recently stated that he believes Ferdinand can continue at United for a few more seasons. "I think Rio can play for two or three more years," the manager said. "He is not as quick as he was but that is not a big issue for me. His experience is important and there is no reason he can't stay on. I didn't even realise his contract was up."

But Ferdinand has since told Inside United: "The best thing I can do is to look at it at Christmas, and then again in the summer, to see how I'm feeling and go from there. But hearing the manager say things like that definitely puts the spring back in your step.

"I'll have a better idea of that in December or January time, when the games start coming thick and fast. That is when it really hits you and you know the hard work really has to start. I'll probably get a better gauge of where I'm at fitness-wise and the benefit of having the summer off then."

Despite a long-standing back condition that means Ferdinand has to manage his fitness, the centre-back does not consider it a big issue and is intent on playing for as long as possible. He was heartened by the 38 appearances he managed in all competitions last season and this term he has missed only two of United's 12 league games, forming a partnership with Jonny Evans.

While the defender's stance may be a negotiating move, his current deliberations could potentially hang on whether he is tempted by a fresh challenge at the close of his career.

There has been at least one recent offer from China for Ferdinand to consider. Currently earning around £130,000 a week, a move there would prove to be highly lucrative for the 81-times capped former England defender.

Nicolas Anelka left Chelsea for Shanghai Shenhua in January for around £175,000 a week, and Didier Drogba joined him in the summer on a two-and-a-half year deal worth a reported $310,000 (£195,000) a week.

Regarding Ferdinand's comments on his future at United, Ferguson said last Friday: "It will sort itself out, I am sure."