Brussels (AFP) - Belgium's constitutional court gave the green light Wednesday to legal action by a sculptor to prove her claim she is the natural daughter of former King Albert II.
The court ruled as unconstitutional some stipulations of Belgian law which could have prevented the case from proceeding.
Delphine Boel, who claims she was born in 1968 after a long affair between her mother, Sibylle de Selys Longchamps and then crown prince Albert, launched proceedings before a top Brussels court in 2013 to have his paternity recognised.
The 81-year-old former monarch, who reigned from 1993 until 2013, has always refused to acknowledge that he could be her father.
In late 2014, the court asked two questions of the constitutional court, which on Wednesday ruled in favour of the arguments made by Boel's lawyers against those of Albert II.
A person who has been declared the child of their mother's husband can contest that man's paternity, the constitutional tribunal ruled, contradicting Belgian's civil code.
In other words, Boel can contest whether the husband of her mother, Jacques Boel, is her father, even if he considered her his daughter throughout her childhood.
The top tribunal also rejected Albert II's lawyers' claims that Boel had waited too long to launch her legal action, ruling that the statute of limitations set by the law was also unconstitutional.
In September 2014, DNA tests confirmed that Jacques Boel was not Delphine's biological father, according to her lawyer Theodora Baum.
As a result of Wednesday's ruling, Boel, aged 48, can pursue her claim against the ex-monarch, who since his July 2013 abdication in favour of his son Philippe no longer enjoys legal immunity.
Albert II admitted in 1999 that his marriage went through a "crisis" in the 1960s and 70s. But royal household lawyer Guy Hiernaux said in 2013 that photos published in the Belgian press showing Albert II with Delphine Boel "do not prove" that he is her father.
The monarchy holds a key position in Belgium, a country sharply divided between its French- and Flemish-speaking halves. It regularly features in gossip magazines, not always in the most favourable light.