Infanta Cristina, 58, and Iñaki Urdangarin, 56, finalised their divorce in December, it has been confirmed.
The former couple signed the papers at a notary office in Barcelona, HELLO!'s sister publication HOLA! exclusively reports.
Their split was confirmed in January 2022 just days after former handball player Iñaki was pictured holding hands with another woman.
She was later revealed to be his co-worker at Imaz & Asociados law firm - Ainhoa Armentia.
According to HOLA! Iñaki and Ainhoa now have an apartment together in Vitoria, where he now works at a small construction company.
Iñaki and Infanta Cristina formally ended their marriage after 26 years together. They first met during the Atlanta Summer Olympic Games in 1996 and tied the knot at Barcelona Cathedral on 4 October 1997.
The bride, who is the older sister of King Felipe of Spain. wore an off-the-shoulder long-sleeved wedding dress designed by Lorenzo Caprile. She accessorised her bridal look with the Spanish Floral Tiara.
The couple became parents in 1999 with the birth of their eldest son, Juan, in 1999, followed by Pablo in 2000, Miguel in 2002 and daughter Irene in 2005.
In June 2018, Iñaki was given a five year and ten-month prison sentence following convictions of embezzlement and money laundering in excess of £4.5 million through his non-profit organisation, the Noos Institute. In 2021, he was put on supervised release, needing to visit prison only once a week.
Infanta Cristina was also investigated but acquitted of any charges. However, King Felipe issued a decree stripping his sister of the title of Duchess of Palma in 2015.
The news of his sister's divorce came as King Felipe and Queen Letizia stepped out at the International Tourism Trade Fair in Madrid on Wednesday.
Letizia looked elegant in a black jumpsuit with blouse-style detailing, while Felipe donned a grey suit and a red tie.
Their eldest daughter, Princess Leonor, 18, is currently in the middle of her military training while their youngest, Infanta Sofia, 16, is studying for her International Baccalaureate at UWC Atlantic College in Wales.
King Felipe will celebrate the tenth year of his reign on 19 June 2024. He succeeded his father as monarch after Juan Carlos I's abdication.
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