A week ago Peter - who declined to give his full name for fear of reprisals from pet-owning neighbours - spread lion dung all over his garden.

It is upsetting because I would like to be able to use my garden more fully

Peter

The Cats Protection League claims this is the best safe method of keeping pesky cats at bay.

The droppings are called Silent Roar, and can be bought at garden centres and pet shops.

But are they effective?

"No, it hasn't worked," Peter said. "It's very surprising because it's obviously a strong deterrent."

He added that eyes were following him as he laid down Silent Roar.

"It was quite frightening," he said. "Two of the cats next door were actually watching me putting the dung down. You could feel that they were thinking 'what is he getting up to? It won't work'. And it hasn't.

"They sniffed. They were suspicious, and eventually they thought 'it doesn't bother us' and they moved on. But they're around, they're wandering."

Orange peel

Peter also tried another technique recommended by the Cat Protection League - orange peel soaked in eucalyptus.

"It looks pretty," he said. "But again, the measure doesn't work."

Peter has already turned his garden into a fortress of high fences and wire mesh as a result of the cats.

A cat charity had described lion faeces as "the ultimate weapon"

The London home owner described the failure of the CPL's techniques as "upsetting".

"I would like to be able to use my garden more fully," he said.

But the league's chief executive encouraged Peter not to give up hope.

"Maybe a few prickly plants about the place might help," Derek Conway told the BBC Radio 4's Today programme.

Cat colony

Mr Conway said the sheer volume of cats inhabiting Peter's garden is probably to blame for the failure of Silent Roar.

"He's got a little bit of a colony that seems to have taken a bit of a shine to his garden," he said.

Mr Conway warned members of the public against putting down poison or taking up air rifles in the fight against felines.

Cats are protected by law, and it is an offence to attack them.

Peter said he would never have considered such extreme measures.

"No," he said. "I'm going to work with the cats. We're going to work and improve the deterrence and just keep trying until we come up with something."