King Philippe of Belgium met his half-sister Princess Delphine de Saxe-Cobourg Gotha for the first time on Friday at Castle of Laeken. After their meeting, the estranged siblings shared a joint message on the Belgian royal family's official social media handles. The duo called it a "warm meeting" and "the opportunity to get to know each other".

"On Friday 9 October we met for the first time at the Castle of Laeken. It was a warm meeting. This extensive and special conversation gave us the opportunity to get to know each other. We have spoken about our own lives and our common interests. This band will develop further in family context," reads the message.

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Gezamenlijke boodschap van de Koning en Prinses Delphine: Op vrijdag 9 oktober hebben wij elkaar voor de eerste maal ontmoet in het Kasteel van Laken. Het was een warme ontmoeting. Dit uitgebreid en bijzonder gesprek gaf ons de gelegenheid om elkaar te leren kennen. We hebben gesproken over onze eigen levens en onze gemeenschappelijke interesses. Deze band zal zich verder in familieverband ontwikkelen. Filip & Delphine ————— Message commun du Roi et de la Princesse Delphine : Ce vendredi 9 octobre, nous nous sommes rencontrés pour la première fois au Château de Laeken. Notre rencontre fut chaleureuse. Nous avons eu l’occasion d’apprendre à nous connaître lors d’un long et riche échange qui nous a permis de parler de nos vies respectives et de nos centres d’intérêt communs. Ce lien va désormais se développer dans un cadre familial. Philippe & Delphine ————— Joint communication of the King and Princess Delphine: On Friday 9 October, we met each other for the first time at the Castle of Laken. It was a warm encounter. This long and rich discussion gave us the opportunity to learn to know each other. We talked about our respective lives and areas of shared interest. This bond will further develop within the family setting. Philippe & Delphine 📷 Koninklijk Paleis / Palais Royal

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Delphine was granted the title of Princess of Belgium following a court battle earlier this month. She is the daughter of King Albert II and Baroness Sybille de Selys Longchamps' 18-year-long affair.

Rumours of King Albert II of Belgium fathering a child with another woman first emerged back in 1999. These were after claims were made in an unauthorised biography about Albert's wife, Queen Paola.

King Albert admitted that he is the father of an illegitimate daughter in January. The 85-year-old fought the paternity claim by 51-year-old artist Delphine for more than a decade.

In a statement released by his lawyers at the beginning of the year, Albert was said to have "learnt the results of the DNA test... [and] the scientific conclusions indicate that he is the biological father of Mrs Delphine Boël".

Delphine first publicly alleged that Albert was her biological father in a 2005 interview. However, it was after he abdicated in 2013 that she opened court proceedings.

Belgium royals
Belgium's King Philippe greets the crowd after a religious service (Te Deum) at the Sainte-Gudule cathedral on Belgian national day in Brussels Francois Lenoir/ Reuters

Her mother, Baroness Longchamps, has stated that she had an affair with the royal between 1966 and 1984, when he was still Prince Albert of Liege.