Caressing a cat may seem a good way to show affection but it can leave a pet stressed out, says a new report.

Constant stroking is disliked by all felines although some put up with it, the study shows.

"Cats who tolerate rather than enjoy or dislike being petted seem to be the most stressed," said Professor Daniel Mills, of Lincoln university.

He also found that, contrary to popular perception, cats are not solitary creatures.

Prof Mills added: "Many people keep groups of cats in their home and some people have argued that because this is an unnatural setup, it is not good for their welfare.

"Our research shows this is not necessarily the case.

"It seems even if they are not best friends, cats may be able to organise themselves to avoid each other without getting stressed."

The research, published in the journal Physiology & Behavior, said cat lovers should avoid constantly stroking their pets and should instead ensure "you give all individuals control over their environment."

The study into the behaviour and emotional state of cats involved teams from the University of Lincoln, the University of Sao Paulo and the University of Veterinary Medicine in Austria.