A digitally-enhanced image of how Madeleine McCann might look now, if still alive, was revealed today.

The image was shown on the Oprah Winfrey show ahead of the US talkshow host's interview with Madeleine's parents, Kate and Gerry McCann, which will be broadcast on Monday.

Sunday will mark two years since Madeleine went missing while on a family holiday in Praia Da Luz, Portugal, and the couple are hoping for renewed public interest and a breakthrough in the case.

They employed a forensic imaging artist, who used computer technology to produce a photographic impression of how the youngster would have aged since she went missing.

It will be used on posters to be distributed worldwide as part of the couple's continuing search for their daughter.

Although Madeleine would still be five today, the image depicts the child at six years of age as her birthday falls in less than two weeks, and her parents did not want it to become out of date quickly.

The expert, at the United States National Centre for Missing and Exploited Children, used photographs of Madeleine's parents at around the same childhood age to produce the "age progression image".

The picture shows a smiling Madeleine, wearing a pink headband in her fair, shoulder-length hair.

The couple believe it is the most realistic image possible of how she might look today, said their spokesman Clarence Mitchell.

"They feel it's important that as many people as possible see Madeleine as she now is, rather than the child of three seen in all of those early photographs," he said.

"This is the child that somebody who is close to Madeleine may spot, rather than the child in those other photos, and Kate and Gerry are incredibly hopeful that this will lead to the phone call that finds Madeleine and brings her home.

"That's why they decided to release it on the Oprah Winfrey show, given the global reach she has.

"It was difficult for Kate to see the image at first, but over time she has got used to it and both Kate and Gerry believe it's the best image possible of what Madeleine may look like now."