Maybe build up to it slowly again. If you're out together or watching a film mention ladies you think are hot, ask his opinion on them. If he engages bring it round to what you'd like to do with them, ask him what he'd like to do. Should be easy enough to persuade him to be fair. Maybe include him in the plans and selection process too next time and don't just present it to him as a done deal. Choosing together could be fun and could build some anticipation. Otherwise it's like. "I've chosen a woman for us, be at this hotel at 8, Bring your dick!"
Bit intimidating