Rice flour is the answer and the technique matters as much as the flour. Rub it into the weave with your palm until the cloth looks slightly grey, rather than sprinkling a layer on top.
A sprinkled layer gets pushed aside by the dough as it settles and then the dough touches fabric. Rubbed in, the flour stays in the gaps and there is no direct contact anywhere.
Same principle if you use a real banneton, incidentally. Most sticking complaints about baskets are dusting complaints.