Disgraced royal Andrew Mountbatten-Windsor has been photographed with what looks like a large purple bruise covering part of his face.

The former Duke of York, who was stripped of his titles last year by his brother King Charles, was driving away from his home at Marsh Farm on Sandringham Estate in Norfolk on Thursday (local time) when he was snapped through the car window.

Images of the “mystery” mark, which appears to cover a large part of Mountbatten-Windsor’s right cheek and around his eye, made front-page news across Britain.

However, the UK Telegraph quoted a “well-placed source” as saying the bruise wasn’t cause for concern, adding there had been “no drama”, accident or attack. They declined to give further details.

The Times, meanwhile, reported that the mark was thought to be “the result of a non-serious medical condition”, while others have speculated it could be related to blood-thinning medication.

Scandal-plagued Mountbatten-Windsor moved to the King’s private Sandringham Estate earlier this year after being evicted from his long-time home, the 30-room Royal Lodge near Windsor Castle.

The former prince has been at the centre of ongoing controversy over his connection to the late sex offender Jeffrey Epstein, with his eviction in February coming shortly after the release of a fresh batch of Epstein-related files by the US Department of Justice.

The files included emails exchanged between Epstein and Mountbatten-Windsor, who also featured in photos that appeared to show him on all fours leaning over a woman lying on the floor.

The former prince Andrew after his arrest in February.

Mountbatten-Windsor was arrested by police on February 19 and questioned over allegations of misconduct in public office. He was later released, and has repeatedly denied any wrongdoing.

According the UK media, Mountbatten-Windsor has hardly been seen in public since a security scare at Sandringham Estate last month.

A balaclava-clad armed man was arrested after allegedly threatening the former prince while he was on a dog walk near his home. It is claimed the man wielded an “offensive weapon” and behaved in an intimidating manner.

The Telegraph reported at the time that Mountbatten-Windsor, who was accompanied by a protection officer on the walk, was “shaken” by the incident.

Thames Valley Police revealed late last month that they were seeking to broaden their investigation into potential offences by the King’s younger brother, including sexual misconduct.

Mountbatten-Windsor paid a ‘peppercorn rent’ for Royal Lodge.

Royal property portfolio

The photos of Mountbatten-Windsor’s bruised face were published as a report by the UK’s spending watchdog revealed fresh details of the royal family’s property arrangements.

Mountbatten-Windsor holds leases for 10 properties, three of which he sublets, while the King pays rent for the former prince’s daughters’ palace homes, according to the National Audit Office (NAO) report.

The watchdog carried out its analysis after the UK parliament’s Public Accounts Committee said last December it would hold an inquiry into the issue amid questions about the lease Mountbatten-Windsor held for the Royal Lodge mansion on Windsor estate.

The issue has been seized on by critics of the monarchy, who increasingly question their wealth.

“We hope that the findings will help correct, clarify or contextualise a number of points regarding royal properties,” a Buckingham Palace spokesperson said.

The NAO said it had examined the property agreements the family had with the Royal Household and with the Crown Estate, a vast property portfolio belonging to the monarchy but which is independently run with all its profits going to the Treasury.

Under a deal struck in 2003, Mountbatten-Windsor obtained a 75-year lease for Royal Lodge in return for a STG1 million ($A1.9 million) upfront payment and a commitment to perform STG7.5 million in renovations, which he duly carried out.

Thereafter, he paid a “peppercorn rent” – effectively nothing – for the mansion and the eight cottages on its 40-hectare estate. He sublet and kept the rent for three of the cottages, which only became unoccupied in April. Neither the NAO nor the Crown Estate, an independent commercial business, had details on that income.

Mountbatten-Windsor paid STG12,922 ($A18,132) a year for another property, Sunninghill Park in Windsor, which was used by a member of ⁠his staff. That lease will end in July next year.

A spokesperson for The Crown Estate said leases with members of the royal family were “in line with independent, professional advice and open market valuations”.

–with Reuters