The parents of missing British girl Madeline McCann are gearing up again to fight claims made by a former Portuguese detective that they faked their daughter's abduction.
Kate and Gerry McCann lost their appeal in the Portuguese Supreme Court earlier this month over a controversial book by Goncalo Amaral, a former detective who was the lead investigator on the case, titled The Truth of the Lie.
Within its pages, Amaral claims three-year-old Maddie's 2007 disappearance from the family's holiday apartment in the seaside town of Praia da Luz was a "cover-up".
He claims there was no abduction, but Maddie had in fact died.
The book was published within days of Portuguese police announcing Maddie's parents were no longer suspects in their daughter's disappearance.
The UK couple took the former detective to court for libel and were awarded $585,000 in damages, only to have the ruling quashed last year.
The Supreme Court backed the previous ruling, but within the finding was the remark that the parents were not "formally in the clear", News Corp reports.
"It should not be said that the appellants were cleared via the ruling announcing the archiving of the criminal case," the court found.
The 78-page ruling added that police ceasing the investigation into the parents "was determined by the fact that public prosecutors hadn't managed to obtain sufficient evidence of the crimes by the appellants".
But the ruling has pushed the McCanns back into the courts, calling the findings "extremely disappointing".
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The couple is lodging a formal complaint while they consider taking their case to the European Court of Human Rights.
But in doing so, the McCanns could be slapped with paying the legal fees for the courts and the author.
"It is eight years since we brought the action, and in that time the landscape has changed dramatically, namely there is now a joint Metropolitan Police and Policia Judiciaria investigation which is what we have always wanted," the McCanns said in a statement.
"The police in both countries continue to work on the basis that there is no evidence Madeleine has come to physical harm.
"We will of course be discussing the implications of the Supreme Court ruling with our lawyers in due course."
The response comes after the McCanns told their lawyers last week not make any public statements regarding the ruling.