"I am so sorry to have to bother you with this, Don Corleone, and I know how busy you are, too busy to deal with a minor matter like this. But if you have a bit of time next week, I would love to take you to lunch and discuss that minor matter of your henchman threatening to torch my store. I'm sure it's just a mistake, or perhaps I misinterpreted his meaning. But it would be such a compliment if you would let me treat you to lunch so that we could straighten out this little matter. Can I call you to set up an appointment? There's a lovely little Italian bistro near here, and I'd love to get your opinion on the gnocchi."
That can be edited down to:
"Hey, Corleone! Call off your thug or else!"
But I don't know... I don't think I'd send the Godfather an abrupt ultimatum like that.