A file of evidence into an alleged cash-for-honours scandal involving a charity based at Dumfries House has been passed by police to the Crown Prosecution Service.

The Metropolitan Police launched an investigation in February, as reported in The Chronicle, following a series of newspaper articles alleging that a donor to The Prince’s Foundation was offered help securing a knighthood.

Anti-monarchy group Republic made a formal complaint to detectives about Charles and former close confidant Michael Fawcett in September 2021, following the stories.

Mr Fawcett, who has since resigned as chief executive of The Prince’s Foundation in the wake of the alleged scandal, had been accused of promising to help a Saudi billionaire donor achieve British citizenship and the honour.

The Met said: “A file was passed to the CPS on October 31.

“The investigation remains ongoing and we will not be providing a running commentary on its progress.”

The force said in September that a man aged in his 50s and a man in his 40s were spoken to under caution on September 6 - two days before the Queen died and Charles became King.

It is understood police have not spoken to the King and have not asked to do so.

The Sunday Times has now reported that prosecutors are expected to decide before Christmas if charges will be brought, with the King’s alleged involvement possibly heard in court.

Last autumn, the Mail on Sunday published a letter from 2017 in which Mr Fawcett reportedly wrote that he was willing to make an application to change businessman Mahfouz Marei Mubarak bin Mahfouz’s honorary CBE to a knighthood, and support his application for citizenship.

The letter, written on headed notepaper in Mr Fawcett’s then-capacity as chief executive of the Dumfries House Trust, said the applications would be made in response to “the most recent and anticipated support” of the trust.

Mr Mahfouz is reported to have donated large sums to restoration projects of particular interest to Charles.

When the investigation was launched, a spokesperson for Charles at Clarence House said the then Duke of Rothesay had “no knowledge of the alleged offer of honours or British citizenship on the basis of donation to his charities”.

Mr Mahfouz is said to deny any wrongdoing.

The Prince's Foundation did not wish to comment.