PSV Eindhoven have accused Manchester United of holding talks with transfer target Arjen Robben without permission.
Robben has scored 16 goals in 48 appearances for PSV
President Harry van Raaij also launched a furious attack on boss Sir Alex Ferguson after Robben visited Old Trafford and United's training complex.
Van Raaij said: "We were very unhappy when we found our player was visiting another club without permission.
"I expected a call from United, but it seems with Ferguson a leopard never changes its spots."
Van Raaij admits United have made a formal declaration of
their interest in the 19-year-old winger to the Dutch club.
But he is unhappy at having had no prior knowledge of Robben's recent visit to Old Trafford.
United have already bought Jaap Stam and Ruud van Nistelrooy from PSV.
And PSV were furious when Stam alleged in his autobiography that he had been tapped up by
Raaij said: "United approached us some months ago about their interest in Arjen but then I heard that Robben was in Manchester and I didn't know anything about that.
"There was absolutely no contact from any United delegate and we are unhappy that we did not know one of our players was visiting another club without our permission.
"I have spoken to the Manchester United chief executive David Gill since I learned of the visit and he was a little embarrassed and said that the initiative was taken by
"I have had good relations with Manchester United in the past over the Ruud van Nistelrooy and Jaap Stam transfers but bad relations with Ferguson.
"I recognise here exactly the same actions as when he approached them both. It is Ferguson's way of doing business but it is not my way.
"You can look back and see similarities to what happened with Stam and Van Nistelrooy. It just seems that, with Ferguson, a leopard never loses its spots."
Raaij added that any move is highly unlikely to happen before next summer and warned he would not sell Robben cheaply.
When a £5m fee was mentioned, he said: "For that money they can get a shirt from Robben with his signature on it, nothing more.
"I will not tell you what cards I have but that figure is a laugh."
Robben said of his trip to Manchester: "My first impression of Ferguson is that he is a nice and good man to deal with.
"What I have seen in Manchester looked good, especially Old Trafford is very impressive.
"It's now up to the clubs and I can't do anything more for the time being."