British detectives working on the Madeleine McCann investigation have revealed that key details in the timeline of her disappearance were wrong.

The revised details will be documented in a new Crimewatch appeal on the case to be broadcast on Monday.

Speaking ahead of the BBC programme, senior investigating officer Detective Chief Inspector Andy Redwood, of the Metropolitan Police, said: "The timeline we have now established has given new significance to sightings and movements of people in and around Praia da Luz at the time of Madeleine's disappearance.

"Our work to date has significantly changed the timeline and the accepted version of events that has been in the public domain to date.

"It has allowed us to work with Crimewatch to build the most detailed reconstruction as yet, and highlight very specific appeal points.

"I hope that when the public see our investigative strands drawn together within the overall context of that appeal, it will bring in new information that moves our investigation forward."

The full reconstruction of the events six years ago when Madeleine went missing starts with a scene of Madeleine's parents Kate and Gerry playing tennis.

Madeleine, dressed in pink shorts, T-shirt and hat, then runs across the court, holding a batch of tennis balls.

In another clip, the McCanns are asked how often they think of their daughter, who went missing when she was three years old on May 3, 2007 from a holiday apartment as her parents dined at a nearby tapas restaurant with friends.

Mr McCann says: "When it's a special occasion, when you should be your happiest and Madeleine's not there, that's when it really hits home. Obviously, Madeleine's birthday goes without saying."

Mrs McCann adds: "It's when you have big family occasions really. That's it isn't it? 'Family occasion' and you haven't got your complete family."

During the programme, DCI Redwood discusses how the police have approached the inquiry.

He says: "Primarily what we sought to do from the beginning is try and draw everything back to zero if you like. Try and take everything back to the beginning and re-analyse and reassess everything, accepting nothing.

"The careful and critical analysis of the timeline has been absolutely key.

"Primarily, we're focused on the area between 8.30pm and 10pm. We know at 8.30pm that was the time Mr and Mrs McCann went down to the tapas area for their dinner and we know that around at 10pm that was when Mrs McCann found that Madeleine was missing."

A number of e-fits are also to be shown in the appeal in a bid to "identify the men and eliminate innocent sightings".

Scotland Yard detectives, who have interviewed 442 people as part of their review-turned-investigation, hope to track down as many people present in the Portuguese town at the time.

Since launching its own investigation, 41 people of interest have been identified by the Met Police, including 15 UK nationals.

Detectives have issued 31 international letters of request to mostly European countries in relation to some of the persons of interest as well as accessing phone records.

A large but "manageable" list of phone numbers identified as being in Praia da Luz - though not necessarily used to make phone calls - has been drawn up by detectives with a "significant" number unattributed to any named person.

British detectives launched a fresh investigation in July this year - two years into a review of the case.

The Met Police now has a team of six Portuguese detectives based in Faro who are carrying out inquiries on its behalf.

The Portuguese investigation is officially closed but authorities there are backing the Scotland Yard inquiry and officers from both countries are working together in pursuing new leads.