Cristiano Ronaldo's representatives in talks with Old Trafford hierarchy over new deal

Having fought off sustained interest from Real Madrid to hold onto the Portugal international during the summer, United manager Sir Alex Ferguson and chief executive David Gill have admitted that next summer will be crucial to deciding Ronaldo's long-term future at the club.

And although United are prepared to wait until the end of the current campaign before drawing up new terms for Ronaldo, who is only 18 months into £125,000-a-week five-year contract, Mendes is understood to have discussed the broad outline of plans to extend Ronaldo's deal should the player reject anticipated overtures from Madrid next summer.

Despite pledging his immediate future to United in August by admitting defeat in his attempt to secure a move to the Bernabeu, Ronaldo has still to win over those supporters angry at his perceived betrayal of the club by openly pursuing a transfer.

Ronaldo's 42 goals in all competitions last season proved the crucial factor in United's success in winning both the Premier League and Champions League and his efforts were recognised with both the PFA and Football Writers' Footballer of the Year awards last May.

Ronaldo, recently voted the FifPro World Player of the Year, is also expected to be crowned European and World Footballer of the Year in the coming weeks. His status as football's leading global figure ensures that Madrid will retain an interest in the player, despite claims by president Ramon Calderon that their pursuit of Ronaldo is over.

United are determined to end the speculation involving Ronaldo and Real by ultimately securing him to a long-term contract that would take him close to the £160,000-a-week package paid to Robinho at Manchester City.

If United fail to tie Ronaldo to a new contract next summer, they risk losing him for the remaining value of his contract – approximately £12 million – in June 2010 if he opts to exploit the obscure Webster ruling – FIFA's Article 17 – that enables players who signed a contract before the age of 28 to buy themselves out of the deal.

The Webster ruling, so-called following Hearts defender Andy Webster's decision to exploit Article 17 in order to move to Wigan Athletic in 2006, has yet to be used by a player at a leading club, but Ferguson admitted earlier this month that he and United are confident that Ronaldo's situation will not result in his exploitation of Webster. Ferguson said: "Next summer will be a key element of his [Ronaldo's] contract situation because he will have three years left then.

"That's comfortable enough because I think the big clubs will shy away from that [Webster ruling] because it could happen to them. I don't think it will be an issue."

Real are close to completing a deal for a player labelled the 'new Ronaldo', however, after holding talks with the 16-year-old Brazilian Alipio Brandao.

Brandao, is currently with Portuguese club Rio Ave and he has also been linked with Chelsea in recent weeks.