Manchester United are on course for another potential contract dispute after Rio Ferdinand’s advisers told the club that he will not discuss a new deal before the summer. United are eager to open talks with Ferdinand over an extension to his contract, which expires at the end of next season, but the England defender’s agent, Pini Zahavi, has instructed that negotiations will not start before the summer.

The Old Trafford hierarchy is hoping that an agreement will be reached quickly at that point, but, given that it took 16 months and considerable angst between opening talks and sealing a deal when Ferdinand signed his present contract, it is apprehensive about the situation. United are also aware that the 29-year-old has expressed an ambition to play in Italy or Spain towards the end of his career and that, because he would be eligible to leave on a free transfer if no deal is agreed by June 2009, he and Zahavi will be in a strong bargaining position when negotiations start.

Ferdinand became United’s biggest earner, on a wage of more than £100,000 a week, when he signed a four-year contract in August 2005, but he was overtaken on the payroll when Cristiano Ronaldo signed a deal worth about £120,000 a week last April. Strong interest in Ronaldo from overseas clubs, most notably Real Madrid, persuaded United to break their wage structure a year ago and, with Ferdinand’s potential availability likely to alert his long-time admirers in Europe — and perhaps at Chelsea — David Gill, the United chief executive, may be on the back foot when he sits down with Zahavi at the end of the season.

United are in the midst of a contract dispute with Wes Brown, whose agent, Paul Martin, has encountered criticism from Sir Alex Ferguson, the manager, for advising his client not to back down as he looks for parity with United’s middle band of earners on about £55,000 a week. United appear content to risk losing Brown on a free transfer in the summer — possibly to Everton, Newcastle United, Tottenham Hotspur or West Ham United — rather than bow to his demands, but if that prospect is unpalatable to Ferguson, the idea of losing Ferdinand to a similar dispute would be worse.

Jean-Michel Aulas, the Lyons president, has suggested that Ferguson “destabilised” Karim Benzema, the highly rated France forward, before the teams met in the first leg of their Champions League first knockout round tie last week.

“When Lyons are interested during a season in a player from another French club, people cry ‘scandal’,” Aulas said. “But when, some days before we play Manchester United, I read here and there that Ferguson wants to make an offer for Benzema — and that is not destabilisation?”

Aulas appears to have been using the Benzema example as a general point, rather than a specific gripe against United. In any case, Ferguson’s interest appears unlikely to come to fruition in the immediate future, with Aulas placing a £70 million valuation on the 20-year-old, who stated this week that he wishes to stay with the French champions next season and preferably move to Italy or Spain thereafter. United may revisit the situation in the summer, but by then Ferdinand’s issue may be a greater priority.