Maddie McCann hasn't been found after vanishing in the Praia da Luz, Portugal, in 2007

 KATE and Gerry McCann are facing the prospect of the inquiry into their daughter Madeleine’s disappearance being halted over funding, it has been reported.

The couple are being kept briefed about the future of Operation Grange, the investigative review set up by New Scotland Yard, after comments by Met Police Commissioner Bernard Hogan-Howe.

He is to ask David Cameron if he wants to continue paying for the investigation, prompting suggestions it could be wound down. Mr Hogan-Howe told a newspaper: “We are still reviewing a lot of material. It is a significant amount of money and we have quite a lot of officers tied up in this. There will be a point at which we and the Government will want to make a decision about what the likely outcome is.

“The Prime Minister agreed to fund this. We have not had any pressure to say, ‘You must stop spending more than x amount’, we have received a lot of support but by Christmas I would want a very clear view of what work is outstanding and what time line there is for that.”

Madeleine vanished from her parents’ holiday villa in Praia da Luz, Portugal, in 2007 when she was three.

The official Portuguese inquiry ended in 2008 and authorities have no plans for another.

However, at the request of Mr Cameron, the Met launched Operation Grange to investigate the little girl’s disappearance.

A total of 28 murder detectives and seven civilian staff are said to have managed to plough through about a quarter of 40,000 pieces of information, both new and old.

So far, the inquiry has cost about £2.5million and the Government has provided an open cheque.

Much of the budget has gone on sending officers to Portugal and Spain to chase leads and on translating Portuguese police files and witness statements.

Mr Hogan-Howe is expected to hear from Downing Street within months on how long funding for the probe is to continue.

In the past, he has said there would be no limit to the amount of time and manpower for the inquiry. However, his latest comments suggest, for the first time, there may be a cap.

Earlier this year, Detective Chief Inspector Andy Redwood, who is leading Operation Grange, said he believed Madeleine had been abducted and could be alive.

A spokesman for the McCanns said: “Kate and Gerry obviously hope the review will continue its work.  

The question of its funding is entirely a matter for the Metropolitan Police and the Home Office.”