A Home Office report into the investigation over the disappearance of Madeleine McCann claims that there was a "distinct lack of trust between all parties" involved.
In a report written by the Child Exploitation and Online Protection Centre on the instructions of the then home secretary Alan Johnson, it said: "Clearly, the McCanns have had a turbulent relationship with both Portuguese and UK law enforcement."
Sky News said that Johnson had asked for the report to be compiled as he needed to decide whether Scotland Yard should be involved in the search for Madeleine after the Portuguese authorities closed their first investigation.
Madeleine was only three years old when she went missing in Praia Da Luz, in Portugal on 3 May 2007. The little girl was left asleep with her two brothers in the ground floor apartment while her parents and friends were in a restaurant 50 metres away.
The McCanns checked on the three children throughout the evening until Kate McCann found Madeleine missing at 10pm.
The report also claims that the McCanns failed to share with police information that was gathered by their own private investigators, who were hired before the close of the first Portuguese investigation.
It said that both Kate and Gerry McCann used monies raised from the Madeleine Fund to hire pirate investigators for three years.
"It is clear that the McCanns and the private investigators working on their behalf have gathered a large amount of information during the course of their enquiries. This information does not appear to have been shared fully with the Leicestershire constabulary or the Portuguese authorities," the report said.
Scotland Yard subsequently launched a review and launched its own investigation into the toddler's disappearance in 2011.
McCanns describe their treatment as inhumane
The report also said that the McCanns described their treatment by the Portuguese police as "inhumane, with no real consideration for their emotional and physical wellbeing."
"Despite the involvement of British consular staff, they were, by their own accounts, left for long periods without any updates or communication with the investigators.
"They state they were taken to the police station on more than one occasion and then left for hours waiting to speak to someone who never materialised," the report said.
Recommendation to set up UK national centre for missing children ignored
The report also made a recommendation that a UK national centre for missing children be established to help coordinate when British children go missing while overseas.
The recommendation went unheeded as Johnson, who had asked and backed the report, was voted out of office in the 2010 General Election, the TV station said.