One of Ireland's most famous tourist attractions has been defaced with a spray-painted mural.

The Cliffs of Moher, which rise 120m (390ft) above the Atlantic on the west coast of County Clare, attract up to 860,000 annually.

The multi-coloured abstract graffiti, measuring 8ft by 6ft, was spotted by a photographer on Monday.

The unknown artist would have taken a considerable risk on the rocks near the Hags Head, the highest point on Moher.

If identified, he or she could face prosecution.

Geologist Dr Eamon Doyle is hopeful it may be possible to remove the graffiti fairly quickly.

'Copycat graffiti'

"The Burren and Cliffs of Moher Geopark have a Leave No Trace policy and would strongly encourage all visitors to support this. As geologist for the Burren and Cliffs of Moher Geopark, my main concern is that this graffiti will lead to other copycat graffiti in more public and vulnerable areas and will detract from the much more important story that lies within the rocks.

"Geologists come from all over the world to study the rocks along the west coast of Clare and among other things we can learn about past climate change and this helps with predicting climate change, something that is affecting us all.

"The cliffs of west Clare are subjected to unrelenting erosion by wind and waves which will remove the graffiti fairly quickly; however we will probably speed up this process manually as we do not want visitors leaving the trails to find it. The cliffs here are very dangerous.

Photographer David Olsthoorn, who photographed the painting, said: "I was down there looking to take some seascape shots during a big storm that was hitting the coast. As I rounded a corner about two-thirds of the way down the cliff, I saw the artwork.

"It definitely looks out of place there among all the natural rock. I think the piece of art itself is quite good. The location, however, is not.

"Painting on natural rock has got a lot of people annoyed. This kind of stuff should really be kept on the streets of the cities."

The graffiti sprayed on the Cliffs of Moher, which made national news and dubbed 'vandalism' by the cleanup team, was painted by a pair of hitchhiking graffiti artists from France - who have just uploaded a video of the process to video-sharing site Vimeo.

The pair, who refer to themselves as 'Mama' and 'Dirty Edoir'are part of a group called Dirty EST, an arts collective based in Paris who focus on graffiti, painting, urban photography, sculpture and short film.

The graffiti was sprayed on Hag's Head area at the cliffs during the pair's road trip throughout Ireland, which they crossed using hitchhiking as a method of travel.

When the graffiti was first discovered a week ago, RTÉ News carried the story on national television. A local geologist said the rocks had 'their own natural beauty' and 'that's what people come to see.'

The video recording also shows the same artists spraying urban areas in Dublin and Galway.