Have you ever walked into a meeting & realized after a few minutes that what you really walked into was a political battle? The other person brought their proverbial swords and chainmail. You brought a notebook or laptop for notes.
Political battles are incredibly frequent in many organizational cultures. It is difficult to give a single recommendation on the approach to take in these situations because each is unique. However, remember to remain calm, ask questions, and if needed, respectively end the meeting with an agreed follow up. That will give your time to reflect and ask for more clarity.