How to END a conversation politely

source: Learn English with Rebecca [engVid RebeccaESL]  2014年3月19日
--"Oh, look at the time. I'm afraid I have another appointment. Let's get together soon, okay? Bye for now. Take care."
--"Well, I won't keep you any longer. You're probably busy." Or, "I'll let you go." Something like that. You could then add something from here. "Let's do lunch sometime"; or "I'll give you a call next week"; and "All right. See you. Bye for now."

(A little more formal situation):
--"It's been a pleasure talking to you." We're in a business situation, right? "It's been a pleasure talking to you." "It's been a pleasure meeting you." "I'll call you next week.", or "May I call you next week?" if you want to, all right?
--"I'll look forward to hearing from you" if that's relevant. Or you could just say, "It's been a pleasure talking to you. Thank you very much." Because in a formal situation, that might be enough.