The prime suspect in the high-profile case of Madeleine McCann's disappearance has declined to be interviewed by the Metropolitan Police, the force has said.

The Met stated that an international letter of request was sent to Christian Brückner, ahead of his imminent release for a separate offence, which he later rejected.

Brückner, a 49-year-old German national, has never been charged with any crime related to the McCann case and denies any involvement.

Madeleine vanished in Praia da Luz, Portugal, in 2007, while her parents, Kate and Gerry McCann, dined at a nearby restaurant, leaving their children sleeping in their holiday apartment.

Brückner is currently serving a seven-year prison sentence for the rape of a 72-year-old woman in Praia da Luz in 2005. He is due to be released soon, as German authorities have indicated.

Detective Chief Inspector Mark Cranwell noted that although the interview request was refused, the investigation into McCann's disappearance and Brückner's role will persist without pause.

The case of Madeleine McCann remains one of the most prominent unsolved missing persons cases globally, with numerous investigations and searches yielding various levels of insight over the years.

Brückner's past includes time spent in Praia da Luz, with his mobile data suggesting he was in the area when McCann disappeared. However, substantial evidence needed to charge him has yet to be found.

Investigators recently conducted extensive searches in and around locations associated with both McCann and Brückner, but these did not lead to any conclusive developments.

While Brückner's case continues to develop, the ongoing investigation showcases the complexities involved in cross-border criminal inquiries between Germany and the UK, especially regarding legal definitions of offenses.