This Europe: House of Orange's apparent unity may peel away in court

The House of Orange has turned crimson with rage over allegations depicting Queen Beatrix as a manipulative snob who falls asleep at parties after too many glasses of wine.

To make matters worse the lid has been lifted not by the "boulevard" press in the Netherlands, but by an insider – the Queen's niece.

Now the feud between Princess Margarita and her husband, Edwin de Roy van Zuydewijn, and the Dutch Royal Family is threatening to spill into the courts.

The couple, who now live in France, allege that a sustained slander campaign against them was orchestrated by the monarch and her court and has ruined their livelihoods.

Mr van Zuydewijn claims to have lost millions of euros in contracts. He and his wife say companies who were on the brink of signing contracts with his Fincentives, a business specialising in personnel options, mysteriously pulled out at the last minute. They claim the reason was pressure from the Dutch Royal Family. Palace insiders say Mr van Zuydewijn was seen as a "dodgy character" who styled himself as a baron. A genealogical expert told a Dutch newspaper his wing of the family had never been titled.

Professor W J Slagter of the Erasmus University in Rotterdam, who runs a legal business, confirmed that a legal action was planned and the couple intended calling 35 witnesses to back up their claim. For two weeks now a Dutch public, unaccustomed to any controversial publicity surrounding its royalty, has been lapping up further instalments of life inside the royal goldfish bowl in the current affairs magazine HP De Tijd.

Princess Margarita, who is the eldest daughter of the Queen's younger sister, Irene, portrayed her aunt as a tyrant who had decreed that Mr van Zuydewijn was unsuitable for marriage. When the couple married in France in 2001 few family members turned up. They claim that whenever they attended family gatherings since then they have been ignored and insulted.

Mr van Zuydewijn told how he was subjected to "psychological terror" around the royal dinner table during an inquisition on his business background. At one royal wedding the Queen ordered him to be removed from the group photograph. At one party they had attended, on the Queen's birthday, the monarch was slumped in a chair asleep and she drank a lot of glasses of wine, Mr van Zuydewijn told the Dutch magazine.

The couple also claimed that their former home in Amstedam was bugged and Mr van Zuydewijn's mail intercepted by the intelligence service.

Queen Beatrix is said to be appalled at the intrusion into the House of Orange's privacy and furious with her niece. The only official statement has been one stating that "out of love for Margarita the family does not wish to comment".

The Dutch royal biographer Fred Lammers, who has written books on Queen Beatrix and Crown Prince Willem Alexander, told The Independent: "This is all a nightmare come true; for years the Queen prided herself on avoiding the type of thing which has so damaged the British monarchy. Now it seems the skeletons are being rattled and, if anything, what's emerging here is even more damaging."