Newcastle chairman Chris Mort has revealed Michael Owen no longer has a buy-out clause in his contract while manager Sam Allardyce wants the England striker to prove his fitness before discussing a new deal.

Owen joined United from Real Madrid for £17million in August 2005 but his career on Tyneside has been blighted by injury so far.

There has been recent speculation about Owen's future, with Manchester City the latest club to be linked with the 27-year-old, but Magpies chairman Mort claims there is no chance he could leave on the cheap.

He said: "There was a clause in Michael's contract which allowed him to leave for a certain fee during the last transfer window and the summer before that as well, but that sort of clause does not exist any longer."

Owen has two years left to run on his lucrative contract but manager Allardyce not anxious to rush into negotiating an extension.

Allardyce said: "I'd like to see him fit for the next 20 games on the trot or more and then enter into a new contract.

"The most important thing is that he's available for selection every week and we can control it.

"Whether that means we lose him at the end of the day or not is non-negotiable because if it happens it happens but we want to see him fit, playing and scoring on a regular basis."

Mort also reiterated that the club have no problem with Owen playing for England, despite reports to the contrary

He said: "It is disappointing because the reality is that Newcastle United are delighted that England regard Michael so highly.

"It is quite right that they should because he is clearly a tremendous striker for his country as well as for Newcastle United.

"I appreciate that the pinnacle of every great player's career is not just representing their club in every way they can, but also representing their country.

"And I wouldn't want to hold any player back in their desire to play for their country.

"Michael is a prized asset to this club and we want to look after him but we appreciate that he wants to represent his country as well."

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