Armand Doorn was quoted as telling the IB Times UK: "A lot of clubs are calling for Demba. At this moment we are doing it [transfer negotiations] with his brother, before we did it alone and now we do it with his brother.
"It is true Manchester United, it's true, but nothing concrete.”
However, Ba has used his Twitter page to completely deny the report, telling his followers: "Really, I don't know how desperate this 'Armand Doorn' can be to talk like he's my agent! He's nothing for me. Stop lying and show respect."
The Senegalese striker, who has joined up with his country for the start of the Africa Cup of Nations, has been a revelation at Newcastle this season, scoring 15 times following his free transfer move from West Ham.
But reports have emerged recently over a release clause in his contract which is alleged to be around the £10 million mark.
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