DO NOT DENY OR CONFIRM ANYTHING, no comment to everything, do not engage in small talk, NO COMMENT.
After this, IF they have any evidence, regardless how flimsy, they must by law produce it, its known as disclosure, you can then prepare your defence accordingly.
It will not go against you saying no comment in the first instance, however anything you say can and will be used in court against you,
You can change your tactics once you know what your up against, but cannot fight an invisible enemy, put them on the back foot to disclose.