Madeleine McCann, three, went missing in May 2007. Picture: AP Photo/PA, File

But Kate and Gerry McCann said retired detective Goncalo Amaral’s “poisonous lies” will never be published in the UK because “no publisher will dare to touch it”.

The retired cop is penning the final pages of his second book on Maddie and wants it to be released by the end of April for “maximum impact” just days ahead of the 10th anniversary of her disappearance.

Kate and Gerry McCann hold an age-progressed police image of their daughter Madeleine during a news conference to mark the fifth anniversary of her disappearance. Picture: Dan Kitwood/Getty ImagesSource:Getty Images

The McCanns expect Mr Amaral — who they say has hampered the global hunt for Maddie with false and malicious accusations while insisting she is dead — will continue being hurtful and controversial in book two.

A family source told The Sun Online: “Madeleine’s parents know that no publisher will dare to touch it in this country under our defamation laws or they would face legal action. Publishers have legal responsibilities.”

A friend of the McCanns warned Mr Amaral their lawyers would get involved if he makes any further slurs against them, after previously alleging they covered up Maddie’s death

“Let’s see what he says this time. He has written another book to coincide with the anniversary. If he repeats any allegations that he has made before, Kate and Gerry’s lawyers will be looking at it. They have said before that their lawyers are watching.

“If Mr Amaral’s attempts to get his current book or his new one about Madeleine published in the UK, lawyers will take immediate action.”

Former Policia Judiciaria (Crime Police) detective Goncalo Amaral, pictured in 2008, is set to release a new book. Picture: AFP/Joao CortesaoSource:AFP

Mr Amaral, who claims to have developed a passion for “writing books and relaxing”, said previously: “I have written another book, examining the timeline and what people have said.”

The book, based on public extracts from Portuguese police files, is expected to give new information about the world’s biggest-ever missing child mystery.

His first offering The Truth of the Lie — written a year after Maddie vanished from a holiday apartment in the Algarve’s Praia da Luz in May 2007 and a bestseller in Portugal — became the subject of a bitter libel feud.

The book, which netted Mr Amaral a reported £350,000 ($568,000) with a combined TV documentary, was never published in Britain and for a time was banned in Portugal during the long-running civil legal battle.

British girl Madeleine McCann vanished from the Portuguese beach resort town of Lagos in 2007. Picture: SuppliedSource:News Limited

He claimed the three-year-old girl died accidentally in the flat and her parents covered up the death and hid her body.

The McCanns vehemently denied his claims, insisting Maddie was kidnapped while left alone with her younger twin siblings as they dined nearby with friends.

A source close to Mr Amaral said: “His second book is being published and is going to come out at the end of April for maximum impact. He thinks it will be a big hit. Mr Amaral knows that the world is fascinated with the Maddie story and her parents.”

Scotland Yard is investigating one “last throw of the dice” lead in a bid to find out what happened to Maddie, and believe she was kidnapped by a European trafficking gang or snatched in burglary gone wrong.

It comes as a petition was launched calling on the McCanns to take a lie-detector test.

This story originally appeared in The Sun and has been republished here with permission.