A work of "guerrilla" art that appeared overnight on the streets of Edinburgh will have to be removed on health and safety grounds.

The 40ft portrait of a hooded man was approved by celebrated French street artist JR and caused a sensation after it was created on steps in the middle of the city.

But officials have said that it will have to be removed before it rains in case it turns into a slippery hazard.

It has been confirmed that the picture was created by students at Edinburgh College of Art. The same group, funded and inspired by French artist JR, were earlier in the week given permission to create massive portraits on University of Edinburgh's McEwan Hall.

Their surprise artwork on the steps of Warriston Close has amazed and delighted locals and tourists alike, who flocked to the area to be photographed.

But the city's director of festival and events, Councillor Steve Cardownie, said the image had to go.

He said: "They are spectacular and we want to give people a chance to see them. We don't want to be killjoys. We're going to leave them till tonight but then they'll have to be removed in case the rain acts with the paste to make the stairs slippy and a health hazard."

Joe Caslin, a student at Edinburgh College of Art, helped create the artwork, said: "JR didn't put it up himself but he saw it and gave it his nod of approval.

"We informed the council a week ago that it was going up in the first place as part of the Inside Out project. It adds to the urban landcape so much more than other things do. The council says it's going to cost lots of money to remove it. But how much does it cost to remove chewing gum?

"It was always meant to be a temporary piece of art and it is incredibly sad that bureaucracy has got in the way."

The council have decided to leave it as long as possible before they take away the artwork to allow people to get a chance to see it.

A spokesman for the local authority said: "We're trying to be flexible so that the artwork can stay in place for longer. Rain was forecast for early Friday morning but that has changed. We do need to remove it before it gets wet, so that people can use the steps safely. The art project involved understands that we have to be responsible and we are talking to them about plans to remove it."

The portrait depicts a hooded man looking out on to the street below. Invisible to people walking down the steps of the close, the image can only be seen from the base of the stairs.

Brigadier David Allfrey MBE, head of the Edinburgh Military Tattoo, spotted the art as he walked past and likened the portrait to "a contemporary Jesus".

He said: "It makes a great statement and must have taken whoever did it hours to do. It's classical Edinburgh random art."

IN DETAIL:

• Inside Out Art Project Photo Gallery