Hugo Klynstra, 21, is the son of Prince Carlos, and the royal's childhood friend Brigette Klynstra.

Prince Carlos Xavier Bourbon de Parma - the cousin of King Willem-Alexander - had arranged with the boy’s mother that the baby would receive no title.

But two decades on, when Hugo turned 18, he decided to overturn the pact so he could claim his birthright.

His father, the prince, has always maintained that Ms Klynstra had the baby of her own free will and made an “independent decision”.

She brought up the boy on her own, but the prince visited them.

The new royal began his legal battle three years ago, determined to become a part of one of the oldest royal families in the world.

He fought a series of legal battles to be granted his royal status and now seeks the outlandish title of 'His Royal Highness Prince Carls Hugo Roderick Sybren de Bourbon de Parne.'

Hugo’s case was granted as being valid by the then Justice minister Ard van der Steur, and last year, a court in the Hague backed the judgement.

He has also demanded that he is listed in a register among other Dutch nobles.

The Council of State, an advisory body to the Dutch Royal famil,y addressed the matter earlier this week. 

The closed-door meeting hashed out what exactly they want Hugo to have - and the decision will be announced in public soon.

His father, Prince Carlos, is married and has three children The Telegraph reports. 

He has never disputed his illegitimate’s son’s quest to join the family during the embarrassing legal and constitutional battle. 

In fact he has made very few public statements on the issue. He did, however, describe it as “sad” and “personal.”

Prince Carlos is the head of the House of Bourbon-Parma.

Under Dutch law, illegitimate royals can claim their families names and titles.