The Observer says United's attempt to sign Berbatov is being frustrated because the north London club are still smarting over Michael Carrick's departure for Old Trafford two summers ago.

"United did to Spurs what Real Madrid are currently doing over Cristiano Ronaldo by forcing the club's hand," a source said.

But the claim was denied by a Spurs executive who insisted there is "no bad blood between the clubs".

The source also said: "He definitely wants to leave but Spurs do not want to sell to United because of Michael Carrick. So, the problem is the price. But the other thing for Spurs is that no other big club is interested."