Handling a recruiter who wants an immediate salary number before sharing the range

A recruiter called about a role but wouldn't share a salary range before asking for my current pay and the minimum I'd accept. I don't want to waste either of our time, yet anchoring the conversation to my present salary seems unhelpful when the responsibilities might be different. I'm considering replying with a range based on the role and asking whether it fits their budget. How do you handle this without turning the first call into an awkward negotiation?