Negotiating

Hi there, I just got a call for a positive feedback phone call for an onsite. And waiting for an email with offer details. While initial phone conversations with recruiter I slightly discussed my current situation and salary but I forgot to tell them I currently have permanent contract and waiting for a bonus for the past year. Do you think it's a good idea to send a prompt email after positive feedback call to "remind" them about my expectations? - I am interested in the company but permanent contract is important. OR should I rather wait for offer first and then "negotiate" via email? I'm based in Europe. Thank you