The parents of Madeleine McCann have denied that they believe their daughter is dead and praised Portuguese detectives for reviewing their investigation into her disappearance.

Kate and Gerry McCann said that they knew of no evidence that their daughter was seriously harmed, despite a series of reports that police have proof that she had been killed.

Mr McCann has used his internet blog to deny reports that the couple now believe their daughter was dead, after her disappearance shortly before her fourth birthday.

“Contrary to some other reports Kate and I do not accept that Madeleine is ‘probably' dead',” he writes. “We know it is a possibility, however the fact there is no evidence Madeleine has been seriously harmed gives us ongoing hope that she will be found alive.”

Mr McCann, a hospital consultant, and his wife, a GP, have been helping to organise a new publicity campaign to promote the international search for Madeleine. A new £80,000 poster campaign will target remote villages in southern Portugal and Spain.

The couple, both 39, from Rothley, Leicestershire, were last month made official suspects in their daughter's disappearance from a holiday apartment in Praia da Luz on May 3. Portuguese detectives believe that Madeleine might have been killed accidentally by Mrs McCann in the flat before the couple disposed of her body and falsified an abduction.

But the new head of the investigation, Paulo Rebelo, has ordered officers to consider all options after a Portuguese judge ruled last month that their was insufficient evidence to reinterview the McCanns.

Mr McCann wrote: “It is very encouraging that Mr Rebelo's officers will be seemingly reviewing all the material in the inquiry, which will hopefully identify areas for further investigation.”

He said that life with their two-year-old twins, Sean and Amelie, was slowly returning to normal and the media frenzy gradually subsiding “with just occasional unsubstantiated reports of ‘evidence' appearing”.

The Times revealed that police in Britain, Germany and Holland have been asked to take DNA samples and fingerprints from holidaymakers who were at the Ocean Club resort when Madeleine disappeared.

Mr Rebelo is also preparing to request that Leicestershire Police arrange for interviews with the seven British friends who were on holiday with the McCanns in Portugal. He wants to clarify their movement on the night that Madeleine disappeared and apparent contradictions in their statements to police.

Portuguese officers took a photocopy of Mrs McCann's diary before the couple left the Algarve which a judge has said can be used as part of the investigation. It was reported yesterday that officers want to seize the laptop computer used by Mr McCann to write his blog and send e-mails while in Portugal. It is currently in Leicestershire.

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