A former car salesman has become a royal prince after Belgium’s Prince Laurent legally recognised him as his biological child.

Clément Vandenkerckhove, aged 26, did not learn who his father was until he was 16 years old when his mother told him, “Your daddy is a Prince.”

Six months ago he was quietly declared as the son of Prince Laurent at an official town hall ceremony, with details now emerging.

According to reports, Vandenkerckhove will not receive a royal allowance or take part in public royal activities, nor will he be part of the royal line of succession.

Vandenkerckhove was the secret love child of the royal and Belgian singer Wendy Van Wanten (real name Iris Vandenkerckhove).

They were in a relationship before Prince Laurent married Princess Claire in 2003.

Vandenkerckhove becomes a half sibling to Princess Louise, 22, and twins Prince Aymeric and Prince Nicolas, 20.

Belgium’s Prince Laurent married Princess Claire after his earlier relationship. Photo: AAP

In September, the young man took part in a Flemish documentary called Clement, Son of… when he came out publicly as the prince’s son.

After the show aired, Prince Laurent released a statement.

“With this announcement, I acknowledge that I am the biological father of Clément Vandenkerckhove.

“We have spoken openly and honestly about this in recent years. This announcement is based on a sense of understanding and respect for those involved. It is the result of joint consultation.

“I kindly request that you receive this information with the discretion that the nature of this intimate matter requires.”

Vandenkerckhove said he was not sure if he would take on his father’s name Saxe-Coburg.

He told Nieuwsblad: “I am proud of the Vandenkerckhove surname.

“To renounce that surname would be a betrayal of everything my mother has done for me.”