Kate and Gerry McCann have issued a renewed plea for anyone in Portugal with information about Madeleine to come forward.

The couple are in Lisbon where they are suing the former lead investigator in the case of their missing daughter, Goncalo Amaral.

Outside court, they held up placards with pictures of Madeleine and a Portuguese telephone number for people to call.

Mrs McCann said: "The important thing to remember is that a child is still missing."

The couple also said they wanted the whole investigation into their daughter's disappearance to be reviewed by Portuguese and British police.

They had earlier heard the final legal arguments in their fight to ban a book written by Mr Amaral.

They will find out next week if the book, which alleges Madeleine died in the family's holiday apartment and her parents faked her abduction, will be banned for good.

The ruling is scheduled for February 18.

Mr McCann said the main reason for fighting the case was to make sure people kept looking for Madeleine.

"If people believe, unnecessarily, that she's dead without any evidence then we'll never find her," he said.

Mr Amaral's lawyers have described the case as an attack on freedom of speech and vowed to go to the European courts if he loses.

The McCanns are pursuing him for about £1m in damages in a separate libel case.

Earlier, the couple revealed they were launching criminal proceedings against a Portuguese TV channel over claims they aired about the death of Madeleine.

TVI broadcast a documentary based on Mr Amaral's book, which was then subject to an injunction.

It is understood the McCanns' lawyer thinks TVI broke the rules of the injunction by continuing to discuss the allegations