A Belgian aristocrat who works as a charity promoter in Edinburgh plans to present himself to the Scottish Parliament as Scotland's King.

The 40-year-old young pretender, who lives in a flat in Edinburgh's New Town, wants a referendum to give him the authority of a ''People's King'' and restore Scotland's monarchy after more than 300 years.

The man who calls himself His Royal Highness Prince Michael James Alexander Stewart of Albany claims to be the great-great-great-great grandson of Bonnie Prince Charlie, and has spent 22 years writing a book to prove it.

With the launch this month of The Forgotten Monarchy of Scotland, Stewart - who was brought up in a chateau in Belgium until his father, Baron Gustave Lafosse, lost the family fortune - will go on chat shows throughout the UK and travel the world, using the book as a platform to stake his claim.

The claim is based on the disputed legitimacy of a son that Charles Edward Stuart had from his relationship with Margaret O'Dea d'Audibert. Stewart claims that Margaret was Bonnie Prince Charlie's second wife and that their son, Edward James Stuart, was a legitimate heir to the throne.

In his book, Stewart says that, when Bonnie Prince Charlie died in 1788, his son, Edward James, was only three years old. He claims that when Bonnie Prince Charlie's brother, Henry Benedict, died, his will said that his nephew, Edward James Stuart, was to inherit his properties in Scotland, France, Ireland and Poland.

Stewart has a vision of a constitutional monarchy for Scotland shaped on the Spanish or Swedish models. As King of Scotland he would not take an automatic role in the nation's politics, but would intervene only if he believed politicians were making policies which were harmful to the people.

The man who despite his royal aspirations describes himself as a socialist said he wants to be a ''People's King'' and would take the crown only with the approval of the Scottish people.

He is biding his time until the elections to the Scottish Parliament next year, and if, as he hopes, the Scottish National Party gains power, he will approach the leaders to call for a referendum on the future of the monarchy in Scotland.

He said: ''If the choice was between a republic and the House of Windsor, all of us would go for a republic - but the people must be given a third alternative. The people must be asked if they would like to introduce the restoration of a constitutional monarchy.''

Dr Alexander Murdoch, a lecturer in 18th century history at Edinburgh University, is unimpressed by the young pretender's claims and dismisses the prospect of a King of Scotland as irrelevant.

He said: ''There is a dispute over the legitimacy of the relationship with the woman from whom the son descends. Michael Stewart claims that there were two wills of Prince Charles's brother, Henry Benedict, which give the indication that the relationship was legitimate and that the off-spring was acknowledged.

''Opposing this is the view that the evidence is too fragmentary and inconclusive. But to me the issue is now completely irrelevant. These dynastic details and points about past monarchies have no relevance to the problems facing Scotland today.''