Check to see if you have aphids. Aphids love to eat new growth and excrete honeydew, which in turn attracts ants.

Soap sprays or insecticidal sprays can be used to kill aphids. You can also shoot a hard spray of water to the plant.

An organic minded store can also provide you with ant solutions like neem oil, cornmeal and other products. They should be ok to use on a potted camellia.

If those are fire ants, you will probably need to use ant poison. I wish I knew of an effective way to get rid of them without poisoning them, but I don't.

Other types of ants I wouldn't worry too much about unless- as Luis suggests- you do have an aphid problem. In which case, the ants should go away once you take care of the aphids.

Luis, another aphid treatment I've seen recommended is a milk and water spray (1 part milk to 3 parts water)- have you heard of this/ tried it?