The illegitimate son of the Dutch king's cousin became an official prince on Wednesday after a ruling by the country's top court.

Prince Carlos de Bourbon de Parme, 48, had taken the justice minister to court in a bid to reverse a 2016 decision to grant his illegitimate son, Hugo Klynstra, permission to use his surname and his title.

But the Council of State ruled in the 21-year-old's favor, allowing him to call himself "His Royal Highness, Prince de Bourbon de Parme."

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Childhood friend

The illegitimate prince was born from a relationship between Prince Carlos and Brigitte Klynstra, a childhood friend. Carlos has claimed that they had agreed their son would not be bestowed any royal status. But when Klynstra turned 18 he applied for recognition.

The Hague court ruled that the circumstances of Klynstra's birth were irrelevant in determining whether he could inherit the royal title.

"Klynstra has the right to change his surname to De Bourbon de Parme and claim the royal title and address," it said, but clarified that it "does not mean Klynstra now becomes a member of the De Bourbon de Parme royal house.

"That is a private matter for the royal house itself."

The elder prince is cousin to Dutch King Willem-Alexander. His grandmother Juliana ruled as queen from 1948-1980.

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Legitimate half-siblings

Price Carlos fathered three legitimate children from his 2010 marriage with journalist Annemarie Gualtherie van Weezel.

The verdict will not change the line of succession to the throne.

The Kingdom of Netherlands was established in 1815. The royal family are meant to remain politically neutral but have traditionally held sway over the formation of government coalitions.

aw/sms (AFP, AP, dpa)

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