The owner of Wales' only working windmill has been ordered to return it to its original colour, after painting it red, white and green.

Melin Llynon on Anglesey was given the makeover to mark the island hosting youth movement Urdd Gobaith Cymru's Eisteddfod - and to look like its mascot Mistar Urdd.

Owner Richard Holt had intended to return it to its original white after the week-long festival of music, dance and literature, but positive reaction stopped him.

He has apologised to Anglesey council but will make a case to keep the new tricolour appearance.

But a descendant of Melin Llynon's first miller said "he would have turned in his grave" if he saw "the colours of the mill now".

Holt said he did not realise he needed permission to redecorate the Grade II-listed structure.

"The original intention was to paint it back white, and I was willing to do that straight after the Eisteddfod," he said.

"But I was amazed by the positive response to the new colours - hundreds said they liked it."

This year was the first time it has been on Anglesey since 2004, and like many other excited locals, Holt put out decorations in the red, white and green colours of the youth movement and its mascot Mistar Urdd.

"Traditionally mills over the centuries are decorated to mark important occasions," Holt added.

Dr Eiddwen Jones, 85, is the great-great-great-great-great-granddaughter of Thomas Jones, who she said was the first miller at Llynon mill in 1776.

He managed the property in the village of Llanddeusant, Anglesey, until he died in his nineties.

She said the windmill should be repainted in whitewash as it is a historical building, and traditionally "that's how the mills were".

The author, whose family moved from Anglesey to Flintshire 150 years ago, said she did not agree that the windmill was painted in the first place to celebrate the Eisteddfod.

She has visited the windmill several times throughout her life where Thomas Jones' name is painted inside, and said he "would have turned in his grave, I believe," if he had known about its new appearance.

Jones added that it looked "very impressive in its original colour" when driving towards it.

"It's been made fun of now rather than kept the fact that it was a historical building and that people have been working there for a couple of centuries," she said.

Holt said the mill can be hard to find for visitors, as it is not close to the A55 road.

But the new colours have sparked a lot of interest.

With winters especially proving difficult with fewer people coming, he added: "I have a duty to ensure the future of the mill for the next generation."

He apologised to the local authority, saying he "realises that they [the council] are only doing their job and I know that I have broken the rules".

But he added: "I'm struggling and the winter is hard, but painting the mill has attracted more visitors here and helped me pay the bills."

He is gathering the opinions of visitors to the mill this summer to make a case to the council.

Holt believes the paint he used can breathe - and therefore poses less risk to the listed building.

"The second issue is - have I changed the character of the mill?" he added.

"I argue that I have not done that because there was a great tradition over the centuries of decorating mills to mark special occasions, and I am sure that the first miller here back in 1776 would have painted the mill red, white and green if such paint had been available."

Having seen the benefits of increased tourism this summer, Holt believes the colours are beneficial in terms of keeping the mill viable, and allowing him to keep it open.

Anglesey council has asked him to return it to its original white as soon as possible.

In a statement, it said any future application regarding a listed building would need to be decided according to relevant legislation, planning policy and the local authority's duty to protect the historic environment.

It added that comments from the public would be considered as part of the process.

However, because it is a listed building, heritage considerations would carry significant weight, and public support alone would not be able to determine the outcome of the application, the council said.