Proposals at Belgrade's horse racing track to sedate 300 horses during a rock concert have been attacked by Serbian animal rights activists.
The Rolling Stones have never performed in Belgrade
The Rolling Stones are due to play in front of 100,000 people at the Belgrade Hippodrome in July.
Staff at the Hippodrome say they may need to sedate the horses that live in stables near the stage to stop them from panicking.
The plans are being opposed by Serbia's largest animal protection group, Orca.
"Horses differ, just like people," explained Jovanka Prelic, who helps looking after the horses at the hippodrome.
"Some are nervous and more skittish. If they start to panic they'll get sedatives," she said.
New venue call
Orca head Elvir Burazerovic said that "noise and vibrations are the strongest causes of stress to animals".
Animal rights activists demand a different concert venue
But he said sedating the horses was not the answer. He is also against the animals being moved, saying this adds to the stress.
Instead, Mr Burazerovic wants another suitable venue for the concert to be found in Belgrade.
"Surely our big city has enough open spaces where even 150,000 people can fit in," he says.
"We think the Hippodrome should be left to horses."
The sedative that will be used for the horses is called Bensedin in Serbia.
It was a popular prescription during the Nato air strikes in 1999, when many of Belgrade's citizens were on tranquillisers.
The Rolling Stones have never played in Serbia. They had to cancel a concert in 2003 following the assassination of the then Prime Minister, Zoran Djindjic.
They also cancelled last year when guitarist Keith Richards suffered a head injury.