A peer has asked to keep a controversial graffiti mural on the walls of his family's 13th century castle in Ayrshire.
The Earl of Glasgow has written to Historic Scotland asking if the exhibit can remain as a permanent feature of Kelburn Castle in Largs.
The mural features a psychedelic series of interwoven cartoons depicting surreal urban culture.
It was completed by Brazilian graffiti artists in 2007 at a cost of £20,000.
It was permitted by North Ayrshire Council on the understanding that it was temporary.
A three-year limit was put on the graffiti, pending the start of work to replace the harling render on the exterior of the turret.
The castle is located in the grounds of Kelburn Estate, which also houses a country centre open to the public and featuring a series of outdoor attractions.
Last month the mural was named as one of the world's top ten examples of street art by author and designer Tristan Manco - on a par with Banksy's work in Los Angeles and the Favela Morro Da Providencia in Rio de Janeiro.
The latest memorandum of guidance published by Historic Scotland states that owners of listed properties should only use "historically correct colours in a manner which is appropriate to the building".
The Earl of Glasgow, Patrick Boyle, whose family has been in Kelburn Castle for 800 years, has written to Historic Scotland seeking to establish whether it is likely the agency would object if he sought consent from the local authority to allow the graffiti to stay indefinitely.
He said: "In the three years that the mural has been on the castle it has attracted enormous interest from around the world and it is loved by everyone who sees it.
"It has become a landmark and a talking point and it has given the castle and the estate a whole new character."
The peer said he realised there were strict rules governing the preservation of historic buildings, but insisted the graffiti added to the character of the castle rather than diminished it.
He added: "What we now call historic buildings have always been drivers of fashion in architecture and design.
"Features that we now take for granted would have seemed radical in their day. The mural might look a bit outlandish and futuristic but if it provokes interest and makes people smile, why shouldn't it stay?"