Battersea Dogs and Cats Home has warned that an app allowing people to find a new pet based entirely on looks risks reducing animals to disposable items.

PetMatch runs image-recognition technology to match pictures of animals, selected by prospective owners, to an "adoption database".

It has been suggested the app can help owners find replacements for dead pets.

The London rescue centre stressed that people should also research the animal's temperament before adopting.

The centre's head of dog rehoming, Rob Young, told the BBC: "We would not approve of using this as a method of choosing a new pet, largely because you should not be looking to rehome an animal on looks alone."

The developers of the app pointed out that users were still able to carry out further checks before they took an animal home.

Users either upload pictures of their ideal pet to the app or use a pre-loaded image. The app then uses image recognition technology to find matches among a database of animals that are up for adoption.

Mr Young said that it would be possible to find identical matches but warned prospective pet owners to be careful.

He said: "There is a good chance they will behave very differently. They all have their own needs. We work to make sure that each animal gets sent to a home that suits their needs."

Mr Young added: "[Use of the app] points towards dogs and cats becoming disposable items. Getting a direct replacement is not the way we would want people to look at it."

The developers, California-based Superfish, said their algorithms allowed the app to analyse pictures with "no human involvement".

The company, which has been backed by five different venture capital firms to the tune of $19.3m (£11.4m), said PetMatch was a "faster, more intuitive way to bring you closer to finding exactly what you're looking for".