MADELEINE McCANN'S parents have told of their heartache as they face a fourth Christmas without their missing daughter and blasted WikiLeaks "smears" for compounding their hurt.

The controversial website released a diplomatic cable from 2007 which suggested that British police played an active role in helping the Portuguese cops build a case against Kate and Gerry McCann over Madeleine's disappearance in May that year.

The McCanns' Portuguese lawyer Rogerio Alves has said the cable was probably refering to the use of sniffer dogs.

They were sent to examine the family's holiday flat, hire car and other things weeks later and before the couple were made official suspects.

But the McCanns said the WikiLeaks release "has led to the repetition of many unfounded allegations and smears both in the UK and in Portugal in particular".

Writing on their website, the couple said: "This has been seized on as an opportunity by those who wish to compound our suffering and hamper our efforts.

"Those who could help Madeleine but choose to do nothing are also complicit in this injustice.

"Without the love and help from so many good people around the world we would not be able to find the strength to continue the fight to find our daughter.

"This month marks our fourth Christmas without Madeleine.

"We hope with all our hearts that wherever she is, she is safe and well and whoever may be with her is treating her with the love and respect she so deserves.

"We would like to thank all our supporters for staying at our side in spite of the injustices that we continue to be subjected to.

"Madeleine is the person who suffers most from all of this injustice. It is this fact alone which causes us the most distress. It is absolutely heartbreaking.

"Thank you to all those who have signed our petition calling on the UK and Portuguese governments to conduct an independent review of Madeleine's case.

"The petition is still ongoing. If you haven't signed and would like to further the search for Madeleine, please sign our online petition or sign a paper petition form.

"Along with our family, we would like to thank everyone who has sent us Christmas cards, letters, donations and gifts at this difficult time of year.

"It is impossible to find enough positive words to describe such kindness or the hugely important and heart-warming effect it has on us.

"Without any doubt, it helps us immensely and we are incredibly grateful."

Madeleine was nearly four when she disappeared from her family's holiday flat in Praia da Luz in southern Portugal on May 3, 2007, while her parents dined with friends nearby.