The investigation into Madeleine McCann's disappearance is said to be nearing a conclusion, as her family launches a new poster campaign.

The four-year-old's parents, Kate and Gerry McCann, were named as suspects, or arguidos, in the case after she went missing on May 3, 2007 from the resort of Praia da Luz on Portugal's Algarve.

On Wednesday, the country's justice minister Alberto Costa said the police probe is "approaching the conclusion of the process" and added that it is "premature" to say whether the investigation would reveal what happened to Madeleine.

Mr and Mrs McCann's spokesman, Clarence Mitchell, said the couple are waiting for news in light of Mr Costa's comments. It is thought detectives in the case wish to talk again to the couple and the friends they dined with on the evening their daughter disappeared.

Mr Mitchell said: "In light of Mr Costa's comments yesterday and the fact that the police are still intending to come over, we are waiting to hear whether they are coming over to interview the friends or Gerry and Kate."

Mr and Mrs McCann have launched the latest phase in the search for their daughter which they hope will help two other families who have also had children go missing.

The "Don't You Forget" drive involves two A3 mail shots - one showing Madeleine and five-year-old Mari Luz Cortes and one with the Leicestershire youngster and seven-year-old Yeremi Vargas - which were posted out to businesses and public sites across Spain and its islands.

Mari Luz went missing on January 13 in her home town of Huelva, 120 miles from Praia da Luz - where Madeleine went missing. Yeremi disappeared from his home in Gran Canaria on March 10 last year.

Mr Mitchell, said: "As far as we are concerned our search continues every day for Madeleine. We will leave no stone unturned. Our investigators are continuing to follow up leads but we still need public assistance. That's why this latest phase is going out.

"The reason we are including the other two children is out of courtesy to their respective families. They are going through the same agony as Kate and Gerry. Their children are missing in the region in potentially similar circumstances.

"It would be discourteous to the families and odd if we did not mention the two other children. Also, we feel we want to help."

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