Kate and Gerry McCann have spoken of their renewed hope that their daughter Madeleine will be found five years on from her disappearance in Portugal.

Mrs McCann said an ongoing review of the case by Scotland Yard and the release of a new age-progression picture of Madeleine had left them feeling "probably as positive" as they had been for a long time.

"We are realistic. We don't know what has happened but we know there is a very good chance that she could be alive - there is no evidence to the contrary," Mrs McCann told presenter Lorraine Kelly on ITV's Lorraine.

"We know year after year, missing children, children that have been abducted, are found alive."

Her remarks come as the couple, from Rothley, Leicestershire, prepare to mark the anniversary of their daughter's disappearance tomorrow.

It also comes at a time when the couple believe there is a possibility that the case of their daughter's disappearance could be reopened.

Mr McCann, 43, said: "I think the most important thing is that a lot of the investigation opportunities are in Portugal.

"I think it's fairly clear that the case will have to be reopened for those to be pursued adequately.

"I have no doubt about that. It will get reopened."

Above: Scotland Yard released this computer-generated picture of what Madeleine may look like now

However the Portuguese authorities have so far refused to reopen their investigation into how the girl vanished on a family holiday to the Algarve on 3 May 2007.

Detective Chief Inspector Andy Redwood said the Metropolitan Police would like the case to be reopened, but stressed that the decision was one for Portugal.

Redwood, the officer leading the Scotland Yard review, spoke last week of his belief that the case can still be solved and launched a fresh appeal for information.

His team of 37 officers have sifted through 40,000 pieces of information and identified 195 "investigative opportunities".

Mr Redwood has said he believes Madeleine was a victim of stranger abduction and says there is evidence she could still be alive.

Scotland Yard released an age-progressed computer-generated image of Madeleine last month, in an attempt to rejuvenate public awareness.

Speaking of the picture, Mrs McCann said: "I think the most important thing is challenging the assumption that Madeleine is a three- or four-year-old.

"She's nearly nine now. People around us certainly see Madeleine in it, and see elements of us in it, and I think that's a good thing. It's certainly a useful tool, and we're pleased with the image."

Madeleine was nearly four years old when she vanished from her family's holiday apartment in Praia da Luz as her parents dined with friends at a tapas bar nearby.

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