Cats in garden

[clemstac]

Hi I've got a pet rabbit and guinea pig which live outside in a hutch which has a run on it. During the summer the rabbit and guinea pig are constantley in and out of the hutch and in the run.
I have a new neighbour who's garden backs onto ours and he has two cats.
I am constantly, sometimes 5 or 6 times a day, having to chase the cats out of my garden as they are trying to get to the rabbit and guinea pig.
What can i do to keep these cats out of my garden. I am especially worried that something may happen when my husband and i are at work and not there to keep a check on them.