"You do not have to say anything, but it may harm your defence if you do not mention when questioned something which you later rely on in court. Anything you do say may be used as evidence."
"You do not have to say anything, but it may harm your defence if you do not mention now something which will later rely on in court. Anything you do say may be given in evidence."
"I am reporting you for <OFFENCE>. You do not have to say anything, but it may harm your defence if you do not mention NOW something which will later rely on in court. Anything you do say may be given in evidence."
"I am reporting you for the question of prosecuting you for the offence of <OFFENCE>. You do not have to say anything, but it may harm your defence if you do not mention NOW something which will later rely on in court. Anything you do say may be given in evidence."