(CNN) A Spanish judge has ruled that singer Julio Iglesias is the biological father of a 43-year-old Spanish man, in a judgment published on Wednesday.

Judge Jose Miguel Bort Ruiz highlighted a "very obvious physical resemblance" between the singer and Javier Sanchez-Santos, who has spoken publicly about his struggle to be recognized as Iglesias' biological son.

The judge in Valencia said there were enough clues to determine paternity, and cited Iglesias' refusal to "enable the collection of biological evidence" as one of the deciding factors.

The Spanish singer Julio Iglesias, during a concert, 1975, Madrid, Spain.

Julio Iglesias' lawyer Fernando Falomir told CNN the singer would appeal the ruling and said Iglesias wouldn't refuse to submit to a DNA test under certain circumstances as part of the appeals process.

The judge said there was "evidence in the proceedings that, at the approximate time of the applicant's conception, there were certain contacts and dealings between the mother of the latter and that defendant."

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