Kate and Gerry McCann have decided not to axe the controversial private detectives leading the hunt for their missing daughter.

The couple were expected to sever their links with Spanish firm Metodo 3 after a series of gaffes by outspoken boss Francisco Marco.

The agency's six-month contract ran out last week, but the McCanns' spokesman announced today that their relationship with the private eyes will continue.

Missing: Madeleine McCann. Her parents are going to continue using private detectives as they refuse to give up hope of finding her

The couple's multi-millionaire backer, double glazing tycoon Brian Kennedy, will continue to pay Metodo's 3 £8,000-a-month fee on a rolling month-to-month basis.

The Find Madeleine Fund will pick up the Barcelona-based firm's expenses, which have been averaging around £50,000 a month.

Marco, 35, the director general of Metodo 3 and son of its founder Marita Fernandez, made a series of bizarre boasts after being hired last September.

He promised last November he would find Madeleine before the firm's six-month contract expired.

And he sensationally claimed last December in his boldest statement to date that he knew who kidnapped her - and hoped to reunite her with her parents by Christmas.

Dad-of-two Marco has consistently said he believes Madeleine is alive and being held against her will in north Africa.

Relatives of Robert Murat, an official police suspect over the youngster's disappearance along with the McCanns, have accused Metodo 3 of trying to frame him.

Clarence Mitchell, spokesman for the McCanns, confirmed today: "Our relationship with Metodo 3 is continuing.

"They are being kept on on a monthly retainer.

"Brian Kennedy will continue to pay their fee of £8,000.

"The Find Madeleine Fund will continue to pay their operating costs which have averaged about £50,000 a month up until now but have started to fall and will probably continue to do so as the number of leads they need to follow up drops off.

"Some of the comments Mr Marco has made in the past have been a bit extravagant and have caused some embarrassment but that has stopped now.

"Brian Kennedy feels that they are a doing a good job in difficult circumstances with passion and commitment and that is important to us.

"They have also developed a large knowledge base during the six months they have already spent working on the case.

"The Portuguese police might not sanction Metodo 3's activity. But being Spanish and Portuguese speakers working in regions where they have language, cultural and technical ties with the police, the Policia Judiciaria seem at least to tolerate them which is important."

He added: "Metodo 3's six-month contract has ended and the rolling retainer has already kicked in.

"It's unlikely to be reviewed at the end of every month. But it may be that in six or seven months if all the leads dry up, the relationship is reconsidered.

"Kate and Gerry still feel that in the absence of any evidence to the contrary, it's logical to believe their daughter may still be alive."

Sources close to the family were quoted as saying the chances of Metodo 3's contract being renewed were "virtually nil" last December after Mr Marco claimed he was close to reuniting Madeleine with her parents.

He told a Spanish newspaper in an interview he believed she was with paedophiles in an area not far from north Africa and his agency was putting together conclusive proof to local authorities so police could proceed with their arrests.

Critics said he would put Madeleine's life in danger if she was still alive and questioned his motives for telling the press he was on the verge of a major breakthrough before his mystified clients.

And his claim was reported at the time to have provoked a stand-up row with the McCanns who are said to have accused him of harming the chances of finding their daughter safe and well.

Robert Murat's mum Jennifer, 71, has claimed Metodo 3 detectives have spent days following her and accused them of trying to frame the British expat.

Murat's German-born girlfriend Michaela Walczuch, linked to Madeleine McCann's disappearance by witnesses who have phoned the Barcelona-based detective agency's hotline, has also implied they are behind a "dirty tricks" campaign to take the spotlight off Kate and Gerry.

Murat and Walczuch, who had started a fledgling property development company together, deny any involvement in Madeleine's disappearance.

The McCann camp has rejected claims Metodo 3 have generated any false leads.

The Find Madeleine Fund, once at £1.2 million, is now down to £544,000.

Mr Mitchell said: "If spending continues at its current rate and nothing comes in, we'll be down to £407,000 by the end of the month.

"But money is still coming in, albeit more slowly, and we've always been happy with Metodo 3's operational work."